Answer:
the answer is 11 years
Step-by-step explanation:
if school A is graduated 50/years,
the graduated in 11 years is 550
added of graduated 1,700 in 550 is 2,250
if school B is graduated 150/years,
the graduated in 11 years is 1650
added of graduated 600 in 1650 is 2,250
so School A and B is to be equal in 11 years