So we are given that the mean is 42% and the sd (standard deviation) is 8%
Assuming our data is normal we can use the 68-95-99 rule
So one thing you should realize is that 42% + 8% is 50% which is passing. That is one standard deviation higher. So we use:
100 - 68 - 13.5 - 2.35 - 0.15 = 16. That means 16% of students passed the test. Which is terrible. They probably need to hit the books more.
Anyways if you have any question feel free to message me!
Hopes this helps!
Ok if half are female that means 40 than 80 more for each of them because they all produce 80 so 80 times 40 = 3200 your gonna do the same 2 more times because of 3 generations so 3200 times 3 = 9600 in total
60/25 = 12/Y
cross multiply and divide
25 x 12 = 300
300 / 60 = 5
Y = 5 boxes