Mr Rao's age is three times the combined age of his two children. In 5 years, his age will be twice the combined age of the two children then. What is Mr Rao's present age?

15 yearsCorrect answerYour answer30 yearsCorrect answerYour answer45 yearsCorrect answerYour answer50 yearsCorrect answerYour answer

Show the answer and explanation

CorrectNot quiteAnswer C

Correct answer: C

Let the children's combined age be $c$ ; Mr Rao is $3c$ .
In 5 years EACH child is 5 years older, so their combined age becomes $c + 10$ .
$3c + 5 = 2(c + 10)$ , so $c = 15$ .
Mr Rao = $3 \times 15 = 45$ years.

Worth noting

Adding only 5 to the children's combined age gives $3c + 5 = 2(c + 5)$ , $c = 5$ and an age of 15 years. Two children means the total grows by 10.

Ten questions from Ages & Problems on Numbers, at your own pace.

Explanation