Question

I need help with 6 and 7. Thanks!!

Answer 1

4/60 = x/4200Cross multipy
60x = 4(4200)
60x = 16800
divide both sides by 60
x = 280

8/50 = x/4500
50x = 8(4500)
50x = 36000
divide both sides by 50
x = 720

Answer 2

For number 6, you can write a proportion out for the number of phones that are defected out of a certain number of phones, which is equal to (with corresponding numerators and denominators) the number of phones altogether and x, which is the expected amount of total defected phones.