Reena and Usha are presently 24 years and 36 years old, respectively. What was the ratio of Usha’s age to Reena’s age 8 years ago?

Introduction / Context:
Past ratios are computed by subtracting the same number of years from both present ages and then reducing the fraction to lowest terms.

Given Data / Assumptions:

• Reena now = 24; Usha now = 36
• 8 years ago: Reena 16; Usha 28

Concept / Approach:
Form Usha:Reena at that time and simplify.

Step-by-Step Solution:

Verification / Alternative check:
Divide numerator and denominator by 4 to reduce 28 : 16 to 7 : 4.

Why Other Options Are Wrong:
4 : 7, 11 : 8, 8 : 11 do not match 28 : 16.

Common Pitfalls:
Accidentally adding 8 years instead of subtracting when moving to the past.

Final Answer:
7 : 4.