Question 7473
We know that Craig is 24 years younger than his father. 
That means we'll use "X" to represent his father's age and use "X-24" to represent Craig's age:


Craig's father:  X
Craig:  X-24


Now it says that "...in 10 years" so before I do anything else, I need to add 10 to both of their ages. 

(x)+10=(x-24)+10



"...Craig's father will be three times as old as Craig WILL BE"
Since Craig father willl be 3 times as old as Craig will be, we need to multiply 3 to whatever age Craig will be in 10 years...which is denoted as (x-24+10)


(x)+10=(x-24+10)(3)
x+10=(x-14)3
x+10=3x-42


Subtract x from both sides to isolate the 10:
(x+10)-x=(3x-42)-x
10=2x-42


add 42 to both sides to isolate the 2x:
(10)+42=(2x-42)+42
52=2x


divide both sides by 2
{{{52/2}}}={{{(2x)/2}}}

26=x

If x=26 (craig's father's age), then x-24=26-24=2 (craig's age)


Craig=2 years old
Craig's father=26 years old