I think that 30 bulbs are expected to be defective.
Answer:
see explanation
Step-by-step explanation:
let y = f(x) and rearrange making x the subject, that is
y = 5x + 4 ( subtract 4 from both sides )
y - 4 = 5x ( divide both sides by 5 )
= x
Change y back into terms of x
(x) = 
Answer:
2/ 15
Step-by-step explanation:
since the probability is 16/ 120
then we simplify it till it gets 2/15
hope this helps
and good luck!