Answer:
47.5 minutes.
Step-by-step explanation:
Data provided:
p(0) = 0.05
p(1) = 0.25
p(2) = 0.5
p(3) = 0.15
p(4) = 0.05
Time required by each faucet to install = 25 minutes
Therefore,
The expected number of minutes spent by the plumber each day installing faucets
= ∑ ( xp(x) × time )
= ( 0 × 0.05 × 25 ) + ( 1 × 0.25 × 25 ) + ( 2 × 0.5 × 25 ) + ( 3 × 0.15 × 25 ) + ( 4 × 0.05 × 25 )
= 6.25 + 25 + 11.25 + 5
= 47.5 minutes.