Family Ages — “Ravi is 3 years younger than his brother. At his sister’s birth, father was 28 and mother 26. The sister was 4 when the brother was born. What was the father’s age at Ravi’s birth?”

Introduction / Context:
This is a timeline reasoning problem. We place all family events on a single line and move forward in years to align each birth with the parents’ ages, then identify the father’s age at Ravi’s birth.

Given Data / Assumptions:

• At sister’s birth (time T0): father 28, mother 26.
• Sister was 4 when the brother was born ⇒ brother’s birth at T1 = T0 + 4; father then = 28 + 4 = 32.
• Ravi is 3 years younger than his brother ⇒ Ravi’s birth at T2 = T1 + 3 = T0 + 7.
• All ages increase linearly year by year.

Concept / Approach:
Anchor at T0 with known parental ages. Use the “sister 4 at brother’s birth” to reach T1, then add 3 more years for Ravi’s birth at T2. Read off father’s age at T2 directly from the anchored timeline.

Step-by-Step Solution:

Verification / Alternative check:
Gaps are consistent: sister→brother = 4 years; brother→Ravi = 3 years; total sister→Ravi = 7 years; father 28 → 35 matches a 7-year increase.

Why Other Options Are Wrong:
31/29/30/33 misplace one or both intervals (4 years and 3 years) on the father’s age timeline.

Common Pitfalls:
Mixing who is older, or adding 3 years in the wrong direction (to the past rather than the future). Always advance everyone’s age by the same interval when jumping along the timeline.

Final Answer:
35