How long was each sprinkler used

Question

The Thomas Family and the Chen Family each used their sprinklers last summer. The water output for the Thomas family’s sprinkler was 15L per hour. The water output rate for the Chen family’s sprinkler was 40L per hour. The families used their sprinklers for a combined total of 55 hrs resulting in a total water output of 1700L how long was each sprinkler used?

Answer 1

T represents the time the Thomas' was on

55 - T represents the time the Chen's was on

15T + 40(55 - T) = 1700

Can you solve for T and answer?