Huilan is 15 years younger than thomas. the sum of their ages is 33 . what is thomas's age?

Thomas = x
Huilan = x -15 (15 years younger than Thomas' age)
If Huilan (x) + Thomas' age (x-15) equals 33, then ;
x+x -15= 33
2x -15 =33 (do anything (throw -15 to the other side and then divide by 2) to leave x alone)

2x= 33+15

2x = 48
x = 24
Thomas is 24 and Huilan is 24-15 = 9 years old.

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