Question

A doctor sees 210 patients every 3 weeks. At this rate, how many patients will the doctor see in 12 weeks?  

Answer 1

210/3=x/12
cross multiply

3x=2520
divide by on each side

x=840

the doctor will see 840 patients in 12 weeks.

Answer 2

First you divide 12 by 3 to get 4, and then you multiply 210 by 4 to get 840, which is answer C. This is because if it is 210 patients per 3 weeks, 3 goes into 12 weeks 4 times, so you need to multiply. I hope this helps!