Salina currently has an account balance of $1,047.69. Her initial deposit on the account was $630 and it earned 3.9% simple interest. How long has Salina held the account?
A - 17 years
B - 26 years
C - 10 years
D - 43 years
Answer:
A. 17 years
Step-by-step explanation:
Use the simple interest equation, I = prt, where I is the interest money gained, p is the starting amount of money, r is the interest rate in decimal form, and t is the time in years.
Plug in the values to solve for t:
417.69 = (630)(0.039)(t)
417.69 = 24.57t
17 = t
= 17 years
So, the correct answer is A, 17 years
if the numbers x+3,2x+1and x-7are in AP then find x
Answer:
-3
Step-by-step explanation:
If these numbers are part of an arithmetic progression, their differences are the same:
(x -7) -(2x +1) = (2x +1) -(x +3)
-x -8 = x -2
-6 = 2x
-3 = x
___
The numbers in the sequence are 0, -5, -10.
Answer:
x = -3.
Step-by-step explanation:
As it is an Arithmetic Progression the differences between successive terms are common, so:
2x + 1 - (x + 3) = x - 7 - (2x + 1)
2x - x + 1 - 3 = x - 2x - 7 - 1
x - 2 = -x - 8
2x = -8 + 2 = -6
x = -3.
Chris wanted to know how likely he is to win at his favorite carnival game. He conducted 50 tests and won 15 times. What is the probability that he will win next time he plays? All answers are rounded to the nearest hundredth. a.) 0.15 b.) 0.30 c.) 0.50 d.) 0.35 SUBMIT MY ANSWER g
Answer:
b.) 0.30
Step-by-step explanation:
15/50 = 0.3
The amount of money spent on textbooks per year for students is approximately normal.
a. To estimate the population mean, 19 students are randomly selected the sample mean was $390 and the standard deviation was $120. Find a 95% confidence for the population meam.
b. If the confidence level in part a changed from 95% 1to1999%, would the margin of error for the confidence interval (mark one answer): decrease stay the same increase not enough information to answer
c. If the sample size in part a changed from 19 10 22. would the margin of errot for the confidence interval (mark one answer): decrease in stay the same increase in not enough information to answer
d. To estimate the proportion of students who purchase their textbookslused, 500 students were sampled. 210 of these students purchased used textbooks. Find a 99% confidence interval for the proportion of students who purchase used text books.
Answer:a
a
[tex]336.04 < \mu < 443.96[/tex]
b
The margin of error will increase
c
The margin of error will decreases
d
The 99% confidence interval is [tex]0.4107 < p < 0.4293[/tex]
Step-by-step explanation:
From the question we are told that
The sample size [tex]n = 19[/tex]
The sample mean is [tex]\= x = \$\ 390[/tex]
The standard deviation is [tex]\sigma = \$ \ 120[/tex]
Given that the confidence level is 95% then the level of significance is mathematically represented as
[tex]\alpha = 100 - 95[/tex]
[tex]\alpha = 5 \%[/tex]
[tex]\alpha = 0.05[/tex]
Next we obtain the critical value of [tex]\frac{\alpha }{2}[/tex] from the normal distribution table
So
[tex]Z_{\frac{\alpha }{2} } = 1.96[/tex]
The margin of error is mathematically represented as
[tex]E = Z_{\frac{\alpha }{2} } * \frac{\sigma}{\sqrt{n} }[/tex]
=> [tex]E = 1.96 * \frac{120}{\sqrt{19} }[/tex]
=> [tex]E = 53.96[/tex]
The 95% confidence interval is
[tex]\= x - E < \mu < \= x + E[/tex]
=> [tex]390 - 53.96 < \mu < 390 - 53.96[/tex]
=> [tex]336.04 < \mu < 443.96[/tex]
When the confidence level increases the [tex]Z_{\frac{\alpha }{2} }[/tex] also increases which increases the margin of error hence the confidence level becomes wider
Generally the sample size mathematically varies with margin of error as follows
[tex]n \ \ \alpha \ \ \frac{1}{E^2 }[/tex]
So if the sample size increases the margin of error decrease
The sample proportion is mathematically represented as
[tex]\r p = \frac{210}{500}[/tex]
[tex]\r p = 0.42[/tex]
Given that the confidence level is 0.99 the level of significance is [tex]\alpha = 0.01[/tex]
The critical value of [tex]\frac{\alpha }{2}[/tex] from the normal distribution table is
[tex]Z_{\frac{\alpha }{2} } = 2.58[/tex]
Generally the margin of error is mathematically represented as
[tex]E = Z_{\frac{\alpha }{2} }* \sqrt{ \frac{\r p (1- \r p )}{n} }[/tex]
=> [tex]E = 0.42 * \sqrt{ \frac{0.42 (1- 0.42 )}{ 500} }[/tex]
=> [tex]E = 0.0093[/tex]
The 99% confidence interval is
[tex]\r p - E < p < \r p + E[/tex]
[tex]0.42 - 0.0093 < p < 0.42 + 0.0093[/tex]
[tex]0.4107 < p < 0.4293[/tex]
needhdjdjdjdjdjdnhiskdjdjdjdjdjdjjshdjdjdjdjdjdjdjd
9514 1404 393
Answer:
-(√2)/2
Step-by-step explanation:
The expression evaluated at n=a gives the indeterminate form 0/0, so L'Hopital's rule can be used to find the limit. The second expression comes from differentiating numerator and denominator. Then the form with n=a is no longer indeterminate.
[tex]\displaystyle\lim_{n\to a}{\frac{\sqrt{2n}-\sqrt{3n-a}}{\sqrt{n}-\sqrt{a}}}=\lim_{n\to a}{\frac{\frac{2}{2\sqrt{2n}}-\frac{3}{2\sqrt{3n-a}}}{\frac{1}{2\sqrt{n}}-0}}\\\\=\sqrt{a}\left(\frac{2}{\sqrt{2a}}-\frac{3}{\sqrt{3a-a}}}\right)=\boxed{-\frac{1}{\sqrt{2}}}[/tex]
If f(x)=logx, show that f(x+h)-f(x)/h=log[1+h/x]^1/h, h=/=0 (Picture attached, thank you!)
Answer:
Step by step proof shown below.
Step-by-step explanation:
To prove the equation, you need to apply the Logarithm quotient rule and the Logarithm power rule. Here's how the quotient rule looks like.
[tex]log_b(x/y) = log_b(x) - log_b(y)[/tex]
And here's how the power rule looks like
[tex]log_a(x)^n = nlog_a(x)[/tex]
First let's apply the quotient rule.
[tex]\frac{f(x+h)-f(x)}{h} = \frac{log_a(x+h)-log_a(x) }{h} = \frac{log_a(\frac{x+h}{x} )}{h}[/tex]
Now we can do some quick simplification, and apply the power rule.
[tex]\frac{1}{h} log_a(1 + \frac{h}{x} ) = log_a(1+\frac{h}{x} )^\frac{1}{h}[/tex]
You plan to conduct a marketing experiment in which students are to taste one of two different brands of soft drink. Their task is to correctly identify the brand tasted. You select a random sample of 200 students and assume that the students have no ability to distinguish between the two brands. The probability is 90% that the sample percentage is contained within what symmetrical limits of the population percentage
Answer:
the probability is 90% that the sample percentage is contained within 45.5% and 54.5% symmetric limits of the population percentage.
Step-by-step explanation:
From the given information:
Sample size n = 200
The standard deviation for a sampling distribution for two brands are equally likely because the individual has no ability to discriminate between the two soft drinks.
∴
The population proportion [tex]p_o[/tex] = 1/2 = 0.5
NOW;
[tex]\sigma _p = \sqrt{\dfrac{p_o(1-p_o)}{n}}[/tex]
[tex]\sigma _p = \sqrt{\dfrac{0.5(1-0.5)}{200}}[/tex]
[tex]\sigma _p = \sqrt{\dfrac{0.5(0.5)}{200}}[/tex]
[tex]\sigma _p = \sqrt{\dfrac{0.25}{200}}[/tex]
[tex]\sigma _p = \sqrt{0.00125}[/tex]
[tex]\sigma _p = 0.035355[/tex]
However, in order to determine the symmetrical limits of the population percentage given that the z probability is 90%.
we use the Excel function as computed as follows in order to determine the z probability = NORMSINV (0.9)
z value = 1.281552
Now the symmetrical limits of the population percentage can be determined as: ( 1.28, -1.28)
[tex]1.28 = \dfrac{X - 0.5}{0.035355}[/tex]
1.28 × 0.035355 = X - 0.5
0.0452544= X - 0.5
0.0452544 + 0.5 = X
0.5452544 = X
X [tex]\approx[/tex] 0.545
X = 54.5%
[tex]-1.28 = \dfrac{X - 0.5}{0.035355}[/tex]
- 1.28 × 0.035355 = X - 0.5
- 0.0452544= X - 0.5
- 0.0452544 + 0.5 = X
0.4547456 = X
X [tex]\approx[/tex] 0.455
X = 45.5%
Therefore , we can conclude that the probability is 90% that the sample percentage is contained within 45.5% and 54.5% symmetric limits of the population percentage.
Find the value of the variable(s) in each figure. Explain your reasoning. Thank you in advance
Answer:
1. x 55
2. y 117
x 51
3.x39
y116
4.x 18
5.x 48
y 14
for the last one I'm not sure. please give 5 start
Complete the equation describing how x
and y are related
Х у
-2-8
-1 -5
y = [? ]x +
0 -2
1 1
2 4 Enter the answer that
3 7
belongs in [?]
Answer:
3
Step-by-step explanation:
-2=0+x
x¹=-2 (purple one)
4=2x-2
2x=6
x²=3 (green one)
how do you change a hot air baloon descends 200 feet per minute from a altitude of 1000 feet into a algebraic expression.
Plz answer quick will give good rate and thanksss
h(x) = (x - 3)^2 determine which x-value whether it is in the domain of h or not
In domain not in domain
0
3
4
Answer:
Hey there!
All of the values: 0, 3, and 4 are in the domain.
This is because h(x) = (x - 3)^2 is a parabola, or a quadratic. By definition, the domain, or the possible x values of a parabola are infinite.
Hope this helps :)
Write x2 − 2x − 3 = 0 in the form (x − a)2 = b, where a and b are integers. (1 point) (x − 4)2 = 3 (x − 3)2 = 2 (x − 2)2 = 1 (x − 1)2 = 4
Answer:
Answer is (x - 1)² = 4
Step-by-step explanation:
[tex]{ \tt{ {x}^{2} - 2x - 3 = 0}} \\ [/tex]
By completing squares:
[tex]{ \tt{ {x}^{2} - 2x + { (\frac{2}{2} )}^{2} - 3 - {( \frac{2}{2}) }^{2} = 0 }} \\ { \tt{( {x}^{2} - 2x + 1) = 4}} \\ { \tt{(x - 1) {}^{2} = 4 }}[/tex]
[tex]{ \underline{ \sf{ \blue{christ \:† \: alone }}}}[/tex]
How high is a tree that cast a 26ft shadow at the same time a6ft post casts a shadow which is 11ft long
Set up a ratio:
6/11 = x/26
Cross multiply:
11x = 156
Divide both sides by 11:
X = 14.18 feet ( round answer as needed.)
Carl recorded the number of customers who visited his new store during the week:
Day Customers
Monday 17
Tuesday 13
Wednesday 14
Thursday 16
He expected to have 15 customers each day. To answer whether the number of customers follows a uniform distribution, a chi-square test for goodness of fit should be performed. (alpha = 0.10)
What is the chi-squared test statistic? Answers are rounded to the nearest hundredth.
Answer:
The chi - square test can be [tex]\approx[/tex] 0.667
Step-by-step explanation:
From the given data :
The null hypothesis and the alternative hypothesis can be computed as:
Null hypothesis: The number of customers does follow a uniform distribution
Alternative hypothesis: The number of customers does not follow a uniform distribution
We learnt that: Carl recorded the number of customers who visited his new store during the week:
Day Customers
Monday 17
Tuesday 13
Wednesday 14
Thursday 16
The above given data was the observed value.
However, the question progress by stating that : He expected to have 15 customers each day.
Now; we can have an expected value for each customer as:
Observed Value Expected Value
Day Customers
Monday 17 15
Tuesday 13 15
Wednesday 14 15
Thursday 16 15
The Chi square corresponding to each data can be determined by using the formula:
[tex]Chi -square = \dfrac{(observed \ value - expected \ value )^2}{expected \ value}[/tex]
For Monday:
[tex]Chi -square = \dfrac{(17 - 15 )^2}{15}[/tex]
[tex]Chi -square = \dfrac{(2)^2}{15}[/tex]
[tex]Chi - square = \dfrac{4}{15}[/tex]
chi - square = 0.2666666667
For Tuesday :
[tex]Chi -square = \dfrac{(13- 15 )^2}{15}[/tex]
[tex]Chi -square = \dfrac{(-2)^2}{15}[/tex]
[tex]Chi - square = \dfrac{4}{15}[/tex]
chi - square = 0.2666666667
For Wednesday :
[tex]Chi -square = \dfrac{(14- 15 )^2}{15}[/tex]
[tex]Chi -square = \dfrac{(-1 )^2}{15}[/tex]
[tex]Chi -square = \dfrac{(1 )}{15}[/tex]
chi - square = 0.06666666667
For Thursday:
[tex]Chi -square = \dfrac{(16- 15 )^2}{15}[/tex]
[tex]Chi -square = \dfrac{(1 )^2}{15}[/tex]
[tex]Chi -square = \dfrac{(1 )}{15}[/tex]
chi - square = 0.06666666667
Observed Value Expected Value chi - square
Day Customers
Monday 17 15 0.2666666667
Tuesday 13 15 0.2666666667
Wednesday 14 15 0.06666666667
Thursday 16 15 0.06666666667
Total : 0.6666666668
The chi - square test can be [tex]\approx[/tex] 0.667
At level of significance ∝ = 0.10
degree of freedom = n - 1
degree of freedom = 4 - 1
degree of freedom = 3
At ∝ = 0.10 and df = 3
The p - value for the chi - square test statistics is 0.880937
Decision rule: If the p - value is greater than the level of significance , we fail to reject the null hypothesis
Conclusion: Since the p - value is greater than the level of significance , we fail to reject the null hypothesis and conclude that there is insufficient evidence to show that the number of customers does not follows a uniform distribution.
Answer:.67
Step-by-step explanation:
Two balls are drawn in succession out of a box containing 5 red and 4 white balls. Find the probability that at least 1 ball was red, given that the first ball was (Upper A )Replaced before the second draw. (Upper B )Not replaced before the second draw. (A) Find the probability that at least 1 ball was red, given that the first ball was replaced before the second draw. StartFraction 24 Over 49 EndFraction (Simplify your answer. Type an integer or a fraction.) (B) Find the probability that at least 1 ball was red, given that the first ball was not replaced before the second draw.
Answer:
The answer is below
Step-by-step explanation:
The box contains 5 red and 4 white balls.
A) The probability that at least 1 ball was red = P(both are red) + P(first is red and second is white) + P(first is white second is red)
Given that the first ball was (Upper A )Replaced before the second draw:
P(both are red) = P(red) × P(red) = 5/9 × 5/9 = 25/81
P(first is red and second is white) = P(red) × P(white) = 5/9 × 4/9 = 20/81
P(first is white and second is red) = P(white) × P(red) = 4/9 × 5/9 = 20/81
The probability that at least 1 ball was red = 25/81 + 20/81 + 20/81 = 65/81
B) The probability that at least 1 ball was red = P(both are red) + P(first is red and second is white) + P(first is white second is red)
Given that the first ball was not Replaced before the second draw:
P(both are red) = P(red) × P(red) = 5/9 × 4/8 = 20/72 (since it was not replaced after the first draw the number of red ball remaining would be 4 and the total ball remaining would be 8)
P(first is red second is white) = P(red) × P(white) = 5/9 × 4/8 = 20/72
P(first is white and second is red) = P(white) × P(red) = 4/9 × 5/8 = 20/72
The probability that at least 1 ball was red = 20/72 + 20/72 + 20/72 = 60/72
What inequality does this number line show?
find the product
(4\m+m)(4/m-m)
[tex]\\ \sf\longmapsto \dfrac{4}{m+m}\times \dfrac{4}{m-m}[/tex]
[tex]\\ \sf\longmapsto \dfrac{4\times 4}{(m+m)(m-m)}[/tex]
[tex]\boxed{\sf (a-b)(a+b)=a^2-b^2}[/tex]
[tex]\\ \sf\longmapsto \dfrac{16}{m^2-m^2}[/tex]
[tex]\\ \sf\longmapsto \dfrac{16}{0}[/tex]
[tex]\\ \sf\longmapsto \infty[/tex]
Answer:
(16-m^4)/m^2
Step-by-step explanation:
=([tex]\frac{4}{m}[/tex]+m)([tex]\frac{4}{m}[/tex]-m)
=[tex]\frac{4+m^2}{m}[/tex]*[tex]\frac{4-m^2}{m}[/tex] (LCM)
[tex]\frac{16-m^4}{m^2}[/tex] (a-b)(a+b)
Write
801
1000
as a decimal number.
Answer:
0.801
Step-by-step explanation:
Answer:
0.801
Step-by-step explanation:
801/1000 = 0.801
In the figure below. MN is the arc of a circle with center L. If the length of arc MN is 6π, what is the area of sector LMN?
On a number line, the coordinates of X, Y, Z, and W are −7, −2, 2, and 7, respectively. Find the lengths of the two segments below. Then tell whether they are congruent. XY and
Simplify (x + 4)(x2 − 6x + 3). x3 − 14x2 + 3x + 12 x3 − 6x2 − 17x + 12 x3 − 10x2 − 27x + 12 x3 − 2x2 − 21x + 12
Answer:
36 x^3 - 32 x^2 + (x + 4) (x^2 - 6 x + 3).x^3 - 62 x + 12
Step-by-step explanation:
Answer:
x^6-2x^5-21x^4+48x^3-32x^2-62x+12
Step-by-step explanation:
Mark me as brainliest!!!!
HELP ASAP
What is the area of the circle shown below?
Answer:
C
Step-by-step explanation:
The area (A) of a circle is calculated as
A = πr² ( r is the radius )
Here r = 18 cm , thus
A = π × 18² = 324π ≈ 1017.9 cm² → C
Answer:
C.) 1017.9 cm²
Step-by-step explanation:
For a given circle
radius (r) = 18 cm
Now,
Area of Circle
= πr²
= 3.14 × (18)² cm
= 3.14 × 324 cm
= 1017.9 cm²
find the greatest number that divides 56 and 84 exactly
Answer:
28
Step-by-step explanation:
Find the gcf
Which is the graph of the linear inequality 2x – 3y < 12? On a coordinate plane, a solid straight line has a positive slope and goes through (0, negative 4) and (3, negative 2). Everything to the right of the line is shaded. On a coordinate plane, a dashed straight line has a positive slope and goes through (0, negative 4) and (3, negative 2). Everything to the right of the line is shaded. On a coordinate plane, a dashed straight line has a positive slope and goes through (0, negative 4) and (3, negative 2). Everything to the left of the line is shaded.
9514 1404 393
Answer:
(c) On a coordinate plane, a dashed straight line has a positive slope and goes through (0, negative 4) and (3, negative 2). Everything to the left of the line is shaded.
Step-by-step explanation:
The x-coefficient is positive, so we can determine the shading from ...
2x ... < ... (pay attention to the x-term and the inequality symbol)
That is, the solution region will have x values that are less than those on the (dashed) boundary line. Lower x-values are to the left, hence shading is on the left side of the boundary. (That's all you need to know here to make the correct choice.)
_____
Additional comment
If the choices are "above" or "below", then you will want to look at the y-term and the inequality symbol. If the coefficient of the variable of interest is negated (as it is for y here), then you need to consider the inequality symbol reversed: -y < ... ⇔ y > .... Here, that means the shading is above the line. Since the slope of the line is positive, "left" and "above" are the same thing.
Answer:
c
Step-by-step explanation:
E2021
Find x in each triangle. PLZ ANSWER FAST!!!!!!!!!!!
4/17 + 3/10 + 9/20 + 3/11 + 7/15
Answer:
[tex]\frac{19351}{11220}[/tex]
Step-by-step explanation:
[tex]\frac{2640+3366+5049+3060+5236}{11220} = \frac{19251}{11220}[/tex]
X^2-9 can be factored using the formula
Answer:
a^2 - b^2 = (a-b)(a+b)
Step-by-step explanation:
x^2 -9
Rewriting as
x^2 - 3^2
We notice that this is the difference of squares
a^2 - b^2 = (a-b)(a+b)
x^2 - 3^2 = (x-3)(x+3)
The following sample contains the scores of 6 students selected at random in Mathematics and English. Use the scores in English as the dependent variable Y.
Mathematics score (X) 70 92 80 74 65 83
English score 74 84 63 87 78 90
Σx =464 Σy=476 Σx^2= 36354 Σy^2=38254 Σxy= 36926
Find the sample coefficient of determination and interpret.
a. 0.0575 and prediction accuracy is 5.75%
b. 0.2397 and prediction accuracy is 23.97%
c. 0.0575 and prediction accuracy is 94.25%
d. 0.2397 and prediction accuracy is 76.03%
Answer:
d the answer is d
Step-by-step explanation:
determine the results of the following operations
Answer:
[tex]\sqrt[3]{4}\times (\sqrt[3]{16}-10 )[/tex]
Step-by-step explanation:
Let be [tex]\sqrt[3]{64}-\sqrt[3]{32} \times \sqrt[3]{125}[/tex], this expression is simplified as follows:
1) [tex]\sqrt[3]{64}-\sqrt[3]{32} \times \sqrt[3]{125}[/tex] Given
2) [tex]\sqrt[3]{4^{3}}-\sqrt[3]{2^{5}}\times \sqrt[3]{5^{3}}[/tex] Definition of power
3) [tex](4^{3})^{1/3}-(2^{2}\cdot 2^{3})^{1/3}\times (5^{3})^{1/3}[/tex] Definition of n-th root/[tex]a^{b+c}= a^{b}\cdot a^{c}[/tex]/[tex](a^{b})^{c} = a^{b\cdot c}[/tex]
4) [tex]4 - (2^{2})^{1/3}\times 2\times 5[/tex] [tex]a^{b+c}= a^{b}\cdot a^{c}[/tex]/[tex](a\cdot b)^{c} = a^{c}\cdot b^{c}[/tex]
5) [tex]4 - 10\times 4^{1/3}[/tex] Multiplication/Definition of power
6) [tex]4^{1/3}\cdot (4^{2/3}-10)[/tex] Distributive property/[tex]a^{b+c}= a^{b}\cdot a^{c}[/tex]
7) [tex]\sqrt[3]{4}\times [(4^{2})^{1/3}-10][/tex] [tex](a^{b})^{c} = a^{b\cdot c}[/tex]/Definition of n-th root
8) [tex]\sqrt[3]{4}\times (\sqrt[3]{16}-10 )[/tex] Definition of power/Result
Find the equation of the line passing through the point (–1, –2) and perpendicular to the line y = –1∕2x + 5. Question options: A) y = –1∕2x – 5∕2 B) y = 1∕2x – 5∕2 C) y = 2x D) y = –1∕2x
Answer:
The answer is option CStep-by-step explanation:
Equation of a line is y = mx + c
where
m is the slope
c is the y intercept
From the question
y = - 1/2x + 5
Comparing with the general equation above
Slope / m = -1/2
Since the lines are perpendicular to each other the slope of the other line is the negative inverse of the original line
That's
Slope of the perpendicular line = 2
Equation of the line using point (–1, –2) and slope 2 is
y + 2 = 2( x + 1)
y + 2 = 2x + 2
y = 2x + 2 - 2
We have the final answer as
y = 2xHope this helps you
Answer:
C) y = 2x
Step-by-step explanation:
I got it right in the test !!
Suppose there is a 11.3% probability that a randomly selected person aged 30 years or older is a smoker. In addition, there is a 23.3% probability that a randomly selected person aged 30 years or older is male given that he or she smokes. What is the probability that a randomly selected person aged 30 years or older is male and smokes? Would it be unusual to randomly select a person aged 30 years or older who is
male and smokes?
Answer:
2.63%
Step-by-step explanation:
11.3/100*23.3/100*100%