Billy age is 10 years less than 2 times Charlie's age. If Billy is 36 years old, how old is Charlie?
Billy's age = B = 36
Charlie's age= C
10 years less means minus 10, and two times means multiplied by 2.
B = 2C-10
Since B = 36
36= 2C-10
Solving for C:
36+10 = 2C
46=2C
46/2 =C
C= 23
Charlie is 23 years old.