Answer:
First answer is correct and the answer for the second question is a = 30
The value of n in 1/5n+3/5n=7/9 is 35/36
<h3>How to solve the equation?</h3>
The equation is given as:
1/5n+3/5n=7/9
Multiply through by 5
n + 3n = 35/9
Evaluate the sum
4n = 35/9
Divide both sides by 4
n = 35/36
Hence, the value of n in 1/5n+3/5n=7/9 is 35/36
Read more about equations at:
brainly.com/question/723406
#SPJ1
As the mean is E[X] =150 and

= 30, using the normal distribution to get the answer is just using Z. So, what we need is P(X<180).
![Z= \frac{x-E[X]}{\sigma } = \frac{180-150}{30} = \frac{30}{30} = 1](https://tex.z-dn.net/?f=Z%3D%20%20%5Cfrac%7Bx-E%5BX%5D%7D%7B%5Csigma%20%7D%20%3D%20%5Cfrac%7B180-150%7D%7B30%7D%20%3D%20%20%5Cfrac%7B30%7D%7B30%7D%20%3D%201)
P(x<180) = P(z< 1) =

(1) = 0.8413.
Then, just multiplying the amount of books you have, which is 500, with the probability would give how many books are less than 180 pages, being:
Answer:the answer is b
Step-by-step explanation:
Answer:
yassssssss quuuueeeennnnnnn
Step-by-step explanation: