If a 12 years old boy is replaced by a new boy, then the average age of 18 boys increases by 1.5 years. What is the age of the new boy?
Show answer & explanation
Correct answer: D
Explanation
The correct answer is option 4 i.e. 39 years.
| Understanding/Application |
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Average = Sum of all quantities/number of quantities Let the initial average x and the 12 year old boy is replaced by a new whose age is y. |
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ATQ- 18x - 12 + y = 18(x + 1.5) 18x - 12 + y = 18x + 27 y = 27 + 12 = 39 |