Word Problem x2

Question

The sum of the ages of Erik and Tiffany is 57 years. 6 years ago, Erik's age was 2 times Tiffany's age. How old is Erik now?

Answer 1

E = Erik's Age

57 - E = Tiffany's Age

E - 6 = Erik's Age 6 years ago

51 - E = Tiffany's Age 6 years ago

Erik's age six years ago was 2 times Tiffany's age

E - 6 = 2(51-E)

E - 6 = 102 - 2E

3E = 108

E = 36

Erik's age is 36

Answer 2

Assume x is Erik age NOW , and y is Tiffany age NOW

The sum of their ages NOW is:

x + y = 57 ............(1)

6 years ago, Erik age was x-6

and Tiffany age was y-6

and the relation between their ages was

x - 6 = 2 (y-6 )

x -6 = 2y - 12

x - 2y = -12 +6

x - 2y = -6 ............(2)

Subtract equation 2 from equation 1

3y = 63

y = 21

substitute 21 for y in equation 1 and solve for x

x + 21 = 57

x = 36

Check

before 6 years Erik age was 36-6 = 30

and before 6 years Tiffany age was 21-6 = 15

and you can see 30 is two times 15