In a cartons of bulbs, 90% contain no defective bulbs, 5% contain one defective bulb, 3% contain two defective bulbs, and 2% contain three defective bulbs. Find the mean and standard deviation for the number of defective bulbs.

Mean, E(x) = 0.17

Variance, V(x) = 0.12

Step-by-step explanation:

90% contains no defective bulbs, P(X=0) = 0.9

5% contain one defective bulbs, P(X=1) = 0.05

3% contain two defective bulbs, P(X=2) = 0.03

2% contain three defective bulbs, P(X=3) = 0.02

The mean for the number of defective bulbs:

Variance for the defective bulbs:

V(x) = 0.29 - 0.17

V(x) = 0.12

4 packs of water and 7 packs of candy bars

step-by-step explanation:

35x4=140

140/20=7