Question

. The professor counts 21 seats in row 3 and 33 seats in row 7. How many seats are there in row 18?

Answer 1

Answer:

66 seats

Step-by-step explanation:

The rate of increase is ...

(change in seats)/(change in rows) = (33 -21)/(7 -3) = 12/4 = 3 . . . seats/row

Then row 18 will have (18-3)·3 = 45 more seats than row 3, hence ...

21 + 45 = 66 . . . . seats in row 18