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ludmilkaskok [199]

3 years ago

9

Sam borrows money from his brother to buy a new video game. He agrees to pay his brother back the full amount of the loan, plus

an additional $4.50, which is 9% interest. How much did Sam borrow originally?

1 answer:

Olegator [25]3 years ago

7 0

Sam borrowed 50 dollars

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So I have another math question that involves the same problem and so is 7 + 7x the same as 7x+ 7 i think it is but i'm not sure

BartSMP [9]

Answer:

it is

Step-by-step explanation:

because it addition it doesn't matter which way you put it

6 0

2 years ago

Read 2 more answers

A simple random sample of size nequals81 is obtained from a population with mu equals 83 and sigma equals 27. (a) Describe the

Ivanshal [37]

Answer:

a) $\bar X \sim N (\mu, \frac{\sigma}{\sqrt{n}})$

With:

$\mu_{\bar X}= 83$

$\sigma_{\bar X}=\frac{27}{\sqrt{81}}= 3$

b) $z= \frac{89-83}{\frac{27}{\sqrt{81}}}= 2$

$P(Z>2) = 1-P(Z$

c) $z= \frac{75.65-83}{\frac{27}{\sqrt{81}}}= -2.45$

$P(Z$

d) $z= \frac{89.3-83}{\frac{27}{\sqrt{81}}}= 2.1$

$z= \frac{79.4-83}{\frac{27}{\sqrt{81}}}= -1.2$

$P(-1.2$

Step-by-step explanation:

For this case we know the following propoertis for the random variable X

$\mu = 83, \sigma = 27$

We select a sample size of n = 81

Part a

Since the sample size is large enough we can use the central limit distribution and the distribution for the sampel mean on this case would be:

$\bar X \sim N (\mu, \frac{\sigma}{\sqrt{n}})$

With:

$\mu_{\bar X}= 83$

$\sigma_{\bar X}=\frac{27}{\sqrt{81}}= 3$

Part b

We want this probability:

$P(\bar X>89)$

We can use the z score formula given by:

$z = \frac{\bar X -\mu}{\frac{\sigma}{\sqrt{n}}}$

And if we find the z score for 89 we got:

$z= \frac{89-83}{\frac{27}{\sqrt{81}}}= 2$

$P(Z>2) = 1-P(Z$

Part c

$P(\bar X$

We can use the z score formula given by:

$z = \frac{\bar X -\mu}{\frac{\sigma}{\sqrt{n}}}$

And if we find the z score for 75.65 we got:

$z= \frac{75.65-83}{\frac{27}{\sqrt{81}}}= -2.45$

$P(Z$

Part d

We want this probability:

$P(79.4 < \bar X < 89.3)$

We find the z scores:

$z= \frac{89.3-83}{\frac{27}{\sqrt{81}}}= 2.1$

$z= \frac{79.4-83}{\frac{27}{\sqrt{81}}}= -1.2$

$P(-1.2$

8 0

3 years ago

-2x-2+x^2+x+180+-2x-2=180

Dominik [7]

Answer:

x= 4, -1

Step-by-step explanation:

-2x - 2 + x^2 + x + 180 - 2x - 2 = 180

add like terms and put in descending order

x^2 - 3x + 176 = 180

subtract 180 from both sides

x^2 - 3x - 4 = 0

factor out the equation

(x-4)(x+1)=0

solve for x

x-4=0 x+1=0

x=4 x=-1

5 0

3 years ago

the scientists collection that as granite that weighs 74 26/36 lbs, marble that weighs 63 16/34 lbs, and quartz that weighs 81 9

ipn [44]

Answer:

<h2> 6 1/2 lbs</h2>

Step-by-step explanation:

Given the weight of granite to be 74 26/36 lbs,

Weight of quartz is 81 9/40 lbs.

To know how much more quartz weight than the granite, we will take the difference between the weight of quartz and granite as shown.

Weight of quartz - Weight of granite

= 81 9/40 - 74 26/36

= 3,249/40 - 2690/36

= (29, 241 - 26,900)/360

= 2,341/360

= 6 181/360

≈ 6 1/2 lbs

quartz weighs approximately 6 1/2 lbs much more than granite

7 0

3 years ago

a bag contains 6 red 4 blue and 8 green marbles how many of each color should be added so that the total number of marbles is 27

PSYCHO15rus [73]

You would need to add 3 marbles to each group.

4 0

3 years ago