A meeting room has 8 rows of seats. Each row has 15 seats. If 5 rows are full and there are three people in the next row, how many seats are empty? Explain your answer.

Total number of seats = (8 rows) x (15 seats per row) = 120 seats.

Number of occupied seats:

(5 rows) x (15 seats per row) = 75 seats

people sitting alone in next row = 3 seats

Total occupied = (75 + 3) = 78 seats

Empty seats = (total seats) minus (occupied seats) = 120 - 78 = 42 empties