Errors in Practice paper 4

Qn 10 last part
Let Y be the no. of defectives in a sample of 100 rods that meet specification,
Y~B(100,0.008)
Since n is large, np<5,>
Since events of Y are independent, let Y1+Y2~Po(1.6)approx.
P(Y1+Y2>=5)=1-P(Y1+Y2<=4)
using GC =0.0237<0.04
Thus, Mr Tan is likely to place an order.

(Jean, is this your mtd? If no, pls post your mtd too. Thanks. ^^)

Qn11ai
Working correct but answer should 0.0404.


Jia you for your coming Prelims!!! ^^
화이팅! (Hwai-ting!)