In one coffee shop, the round table can seat 9 people and the rectangular table can seat 5 people. During lunch time, all the tables in the coffee shop were occupied. The number of each type of tables in the coffee shop is more than 6 and less than 12. If there were 135 people, find
(a) the number of rectangular tables
(b) the number of round tables
Rectangular tables |
Number of people around rectangular tables |
Round tables |
Number of people around round tables |
Total number of people |
7 |
7 x 5 = 35 |
7 |
7 x 9 = 63 |
35 + 63 = 98 (x) |
8 |
8 x 5 = 40 |
9 |
9 x 9 = 81 |
40 + 81 = 121 (x) |
9 |
9 x 5 = 45 |
10 |
10 x 9 = 90 |
45 + 90 = 135 (✓) |
(a)
Number of rectangular tables = 9
(b)
Number of round tables = 10
Answer(s): (a) 9; (b) 10