You can put this solution on YOUR website! Mr. Tanaka is 35
Son is 5
x years until Mr. Tanaka is 3*son's age:
35+x= 3(5+x) Multiply on right:
35+x= 15+3x Subtract 15 and x on both sides
20= 2x Divide both sides by 2:
10= x
In 10 years, Mr Tanaka will be 35+10= 45 and his son will be 5+10= 15. Divide:
45/15= 3 Mr. Tanaka will be 3 times as old as his son.