Alvin's age is two times Elga's age. The sum of their ages is 63. What is Elga's age?

Answer: Alvin = 42 yrs, Elga = 21 yrs

Step-by-step explanation:

Let Elga's age be x, and Alvin's age be y, since Alvin is two times Elga's age, then

Alvin's age = 2x, that is

y = 2x ... equation 1

The sum of their ages is 63 implies

x + y = 63 ... equation 2

Solving the resulting linear equations by substitution method.

Substitute equation 1 into equation 2, we have

x + 2x = 63

3x = 63

x = 63/3

x = 21

Therefore : Elga is 21 years old, then Alvin will be 21 x 2, which will be 42