Question

Devaughn's age is two times Sydney's age. The sum of the ages is 75. What is Sydney's age?

Answer 1

Devaughn is `50` and Sydney is `25`

Explanation:

Let Devaughn's age be `D` and Sydney's age be `S`

We are told:
[1]`color(white)("XXX")D=2S`
[2]`color(white)("XXX")D+S=75`

From [1] we know we can substitute `2S` for `D` in [2] to get
[3]`color(white)("XXX")2S+S=75`

`rarr`[4]`color(white)("X")3S=75`

`rarr`[5]`color(white)("X")S=25`

From [5] we know we can substitute `25` for `S` in [1] to get
[6]`color(white)("XXX")D= 2 xx 25 =50`