How much is root of five by root of five<br>

If a store advertised a sale that gave customers a 1/4 discount what is the fractional part of the original price that the custo

mina [271]

It will be 3/4 of the original price

8 0

2 years ago

The mean time it takes to walk to the bus stop is 8 minutes (with a standard deviation of 2 minutes) and the mean time it takes

kifflom [539]

We have been given for a normal distribution the mean time it takes to walk to the bus stop is 8 minutes with a standard deviation of 2 minutes. And the mean time it takes for the bus to get to school is 20 minutes with a standard deviation of 4 minutes.

(a) Average time that it would take reach school can be obtained by adding the average times.

8+20 = 28 minutes.

(b) Standard deviation of the trip to school can be found as:

$\sigma =\sqrt{2^{2}+4^{2}}=\sqrt{4+16}=\sqrt{20}=4.47$

Therefore, standard deviation of the entire trip is 4.47 minutes.

(c) Let us first find z score corresponding to 30 minutes. $z=\frac{x-\mu }{\sigma }=\frac{30-28}{4.47}=0.447$

We need to find the probability such that $P(x>30)=P(z>0.447)=0.67$

Therefore, the required probability is 0.67.

(d) If average time to walk to school is 10 minutes, then overall average time for the trip will be 10+20 = 30 minutes.

(e) Standard deviation won't change it will remain 4.47

(f) The new probability will be:

$z=\frac{x-\mu }{\sigma }=\frac{30-90}{4.47}=0$

$P(x>30)=P(z>0)=0.5$

Therefore, probability will be 0.50.

6 0

3 years ago

Read 2 more answers

A student answers 160 of 200 questions on an exam correctly. What percent of the questions did he answer correctly?

Alexandra [31]

Dive correct answers by total questions:

160/200 = 0.80

Multiply by 100 to get percent:

0.80 x 100 = 80%

5 0

3 years ago

Read 2 more answers

Help please!! first answer gets marked brainliest!

algol [13]

Answer:

Answer 30

Step-by-step explanation:

if you need to solve or see step- by step explanation here's a link https://mathsolver.microsoft.com/en/solve-problem/%60sqrt%7B%2050%20%20%7D%20%20%20%60times%20%203%20%60sqrt%7B%202%20%20%7D

3 0

2 years ago

Subtract: ( - 2x4 - 4y + 4z² +6) - (-9x4 – 3y + 4z? +9) 0 - 7x² + y + 3 0 - 11x4 - 7 - 3

Vinil7 [7]

Answer:

36x-3y+4z^2+26-7x^2

Step-by-step explanation:

Okay well for starters, you can't subtract that because it's an expression, not an equation. And secondly, there was '?' which I'm going to assue=me was a typing error.

Now to actually simplify this mess of an expression, you just need to combine the like-terms! Once you do that you really can't do anything else, since you don't know the varibles.

5 0

2 years ago