There are several information's already given in the question. based on those information's, the answer can be easily deduced.
a. It is already given that 1% are defective. It is required to find the number that is needed to be checked to get 5 defective products.
Then
1% of X = 5
0.01X = 5
x = 5/0.01
= 500
b. <span>σ = square root [(<span><span><span><span>n^2</span>−1)/</span>12]
= square root [(250000 - 1)/12]
= square root [249999/12]
= square root (20833.25)
= 144.34
= 144
I hope the procedure is clear enough for you to understand. I also hope that this is the answer that you were looking for and the answer has actually come to your desired help.</span></span></span>
9(3+5)
if you go through each answer choice you will notice that none of the rest are right
8(3+6) = 24 +48
8(19 +37) = 152 + 296
9(18 +36)= 162 +324