Friday

April 18, 2014

April 18, 2014

Posted by **Adam** on Wednesday, November 9, 2011 at 6:25am.

- Mathematics -
**Reiny**, Wednesday, November 9, 2011 at 9:41amLet John's present age be x

Four years ago John was x-4

Half of John's age 4 years ago = (x-4)/2

John's age in 5 years from now = x+5

a third of his age 5 from now = (x+5)/3

(x-4)/2 = (x+5)/3

cross-multiply

3x - 12 = 2x + 10

x = 22

So John is now 22 years old

check:

4 years ago he would have been 18

5 years from now he will be 27

is half of 18 equal to a third of 27 ? YES

**Related Questions**

Mathematics - In 11 years, the age of Russel will be half of the square of the ...

Math - The sum of John's age and twice of his son's age is 56. In 8 years time, ...

MATH - SALLYS AGE IS 12 YEARS PLUS HALF HER AGE. HOW OLD IS SHE?

Mathematics - Kari is 10 years old. her sister is half her age. Explain why 10 x...

Mathematics-please help quick!! - Harry is twice as old as Doyle. Doyle's age is...

Math - John's present age is five years more than thrice the present age of his ...

math - 1. Lisa is 15 years old and her father is 40. How many years ago was the ...

math - A. John is now 10 years older than Marcus. Three times John's age 5 years...

mathematics - the average age of a family of six is 25 years.The average age of ...

math - In 11 years, the age of Russel will be half of the square of the age he ...