You are given a question and two statements. Identify which of the statements is/are sufficient to answer the question.
Question:
What is the total age of the sisters 10 years from now?
Statements:
1. Lina is 20 years old now. 2. Lina’s sister’s age is twice that of 1/4th of the age of Lina.
- AOption (a)
Statement 1 alone is sufficient.
- BOption (b)
Statement 1 and 2 together are not sufficient.
- COption (c)
Statement 2 alone is sufficient.
- DOption (d)
Statement 1 and 2 together are sufficient.
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Correct answer
Statement 1 and 2 together are sufficient.
Why this answer is correct
Shortcut Trick
From Statement 1: Lina's age = 20 years.
From Statement 2: Sister's age = 2 × (1/4 × 20) = 10 years.
Total age after 10 years = (20 + 10) + (10 + 10) = 30 + 20 = 50 years.
Both statements are required to find the unique value of the sister's age and the total.
∴ The correct answer is Statement 1 and 2 together are sufficient.
Alternate Method
Given:
Current age of Lina = 20 years (from Statement 1).
Sister's age relation = 2 × (1/4th of Lina's age) (from Statement 2).
Calculations:
⇒ Let L be Lina's age and S be Sister's age.
⇒ L = 20
⇒ S = 2 × (1/4 × 20) = 2 × 5 = 10 years.
⇒ Lina's age after 10 years = 20 + 10 = 30 years.
⇒ Sister's age after 10 years = 10 + 10 = 20 years.
⇒ Total age after 10 years = 30 + 20 = 50 years.
∴ The correct answer is Statement 1 and 2 together are sufficient.
Additional Information
Data Sufficiency Rules
In data sufficiency, if a question asks for a specific value, the statements are sufficient only if they lead to a single unique numerical value.
Age Difference Property
The difference between the ages of two people remains constant throughout their lives, regardless of how many years pass.
Future Age Formula
If the current age is x, then the age after n years is x + n. If there are k people, the sum of their ages increases by k × n after n years.



















