In a group of people, 28% of the members are young while the rest are old. If 65% of the members are literates, and 25% of the literates are young, then the percentage of old people among the illiterates is nearest to

Let the total number of people in the group be 100.

Number of young people = 28
Number of old people = 100 − 28 = 72

Number of literate people = 65% of 100 = 65
Number of illiterate people = 100 − 65 = 35

Out of the literates, 25% are young:
Number of young literates = 25% of 65 = 16.25

Since the total number of young people is 28, the number of young illiterates must be:
Young illiterates = 28 − 16.25 = 11.75

We need to find the percentage of old people among the illiterates. The number of old illiterates is:
Old illiterates = Total illiterates − Young illiterates = 35 − 11.75 = 23.25

The percentage of old people among the illiterates is:
$\frac{23.25}{35}\times 100\approx 66.43\%$

Nearest to 66.