instruction:
You are given a math word problem and you are supposed to make use of mathematical concepts like probability, combinatorics, linear equations, sequences/series, or simple operators like addition, subtraction, division, or multiplication to answer the given question. Choose the best option from the 5 given options and report that option.
question:
Question: The average age of 3 boys is 15 years and their ages are in the proportion 1:2:3. The age of the youngest boy is?

 Option A: 10 years

 Option B: 12 years

 Option C: 15 years

 Option D: 18 years

 Option E: 7.5 years
answer:
Option E


question:
Question: An inspector rejects 15% of the meters as defective. How many will he examine to reject 15?

 Option A: A

 Option B: B

 Option C: C

 Option D: D

 Option E: E
answer:
Option A


question:
Question: Bat is bought for Rs.400 and sold at a gain of 20% find its selling price?

 Option A: Rs.320

 Option B: Rs.350

 Option C: Rs.370

 Option D: Rs.480

 Option E: None of these
answer:

Option D