Difficulty: Easy
Correct Answer: 40 years
Explanation:
Introduction / Context:
This is a standard aptitude question on ages involving a ratio between the present ages of two people and information about one person's age in the past. Our goal is to use this data to find Renuka's present age and then compute her age after 5 more years.
Given Data / Assumptions:
Concept / Approach:
First we convert the past information about Sony's age into her present age. Then we apply the given ratio of present ages to calculate Renuka's current age. Finally, we add 5 years to Renuka's present age to obtain her age in the future. The problem mainly uses ratios and basic linear equations.
Step-by-Step Solution:
Step 1: Sony's age four years ago was 24 years.
Step 2: Sony's present age = 24 + 4 = 28 years.
Step 3: Let Renuka's present age be R years. Using the ratio R : 28 = 5 : 4.
Step 4: From R / 28 = 5 / 4, we get 4R = 5 × 28 = 140.
Step 5: Therefore, R = 140 / 4 = 35 years.
Step 6: Renuka's age after 5 years = 35 + 5 = 40 years.
Verification / Alternative check:
Check the ratio using the found ages: 35 : 28. Dividing both by 7 gives 5 : 4, which matches the question. Adding 5 years to 35 gives 40, confirming the result.
Why Other Options Are Wrong:
30 years, 35 years, 38 years, and 45 years do not match Renuka's age 5 years from now once the correct present ages are calculated. Only 40 years is consistent with the ratio and time conditions given.
Common Pitfalls:
Students often forget to shift from "four years ago" to the present age correctly or stop after finding the present age of Renuka without adding the required 5 years. Always track the time references carefully.
Final Answer:
Renuka's age after 5 years will be 40 years.
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