You can put this solution on YOUR website! Let a = Al's present age
Let b = Bob's present age
:
Write an equation for each statement:
"Last year Al was 6 times Bob's age"
a - 1 = 6(b - 1)
a - 1 = 6b - 6
a = 6b- 6 + 1
a = 6b - 5
:
"In 3 years Al will be (3 X Bob's) + 10"
a + 3 = 3(b+3) + 10
a + 3 = 3b + 9 + 10
a + 3 = 3b + 19
a = 3b + 19 - 3
a = 3b + 16
:
Substitute (6b-5) for a in the above equaion
6b - 5 = 3b + 16
6b - 3b = 16 + 5
3b = 21
b =
b = 7 yrs old is Bob
:
Use equation: a = 6b - 5 to find a
a = 6(7) - 5
a = 37 yrs is Al's age
;
:
Check solution in the last statement
a + 3 = 3(b+3) + 10
37 + 3 = 3(7 + 3) + 10
40 = 30 + 10
