0.128 ; 0.872 ; 0.748 ; 0.124 ; 0.252

Step-by-step explanation:

Given the data above ;

The frequency distribution generated for the number of defects observed on each of 250 lcd screens are as follows :

__number of defects___frequency

0 24

1 82

2 38

3 43

4 31

5 26

6 6

A.) . What proportion of the screens have more than 4 defects? Give your answer to three decimal places.

More than 4 defects = (number of 5 defects + 6 defects) / total number of defects)

(26 + 6) / 250 = 32 / 250 = 0.128

b. What propotion of the screens have at most 4 defects? Give your answer to three decimal places.

Number of (0 + 1 + 2 + 3 + 4) defects

= (24 + 82 + 38 + 43 + 31) / 250

= 218 / 250 = 0.872

c. What proportion of the screens have fewer than 4 defects? Give your answer to three decimal places.

Number of (0 + 1 + 2 + 3) defects

= (24 + 82 + 38 + 43) / 250

= 187 / 250 = 0.748

d. What proportion of the screens have exactly 4 defects? Give your answer to three decimal places.

Number of 4 defects = 31

= 31 / 250

= 0.124

e. What proportion of the screens have at least 4 defects? Give your answer to three decimal places.

Number of (4 + 5 + 6) defects

= (31 + 26 + 6) / 250

= 63 / 250

= 0.252