Answer: 3
Step-by-step explanation:
Given : A manufacturer of window frames knows from past experience that 15 per cent of the production will have some type of minor defect that will require adjustment.
i.e. the proportion of production will have some type of minor defect that will require adjustment. : p=0.15
If n=20 windows are selected at random , then the expected number of window frames have minor defects = np
[tex]=20\times0.15=3[/tex]
Hence, the expected number of window frames have minor defects =3