Explanation

Let the family earnings in May = $100

Mrs. Lee earned 60% of 100 = $60

The rest of the family earned 100 - 60 = $40


In June, Mrs. Lee earned 20% more = \(60 \space * \space \frac{120}{100} = $72\)

The rest of the family had no change in their earnings, and hence their earning was still $40.

Therefore, in June, the total Family's earnings was $112 of which Mrs. Lee earned $72


\(\frac{Percentage}{100} \space * \space Total = Portion\)

\(\frac{Percentage}{100} \space * \space 112 = 72\)

% = \(\frac{72}{112} \space * \space100 = 64.28 \space \approx 64\)%


Option A