Question 892922
let a = A's age
let b = brother's age
:
Write an equation for each statement.
:
"Alfred is three times as old  as his brother."
a = 3b
:
"Six years ago, the sum of their ages was equal to Alfred's present age."
(a-6)+(b-6) = a
a + b - 12 = a
a - a + b = 12
b = 12 yrs is brothers age
then
3(12) = 36 is A's age
:
:
See if that works in the 2nd sentence
6 yrs ago, their ages:
30 + 6 = 36