In one canteen, the round table can seat 7 customers and the oval table can seat 5 customers. During lunch time, all the tables in the canteen were occupied. The number of each type of tables in the canteen is more than 6 and less than 13. If there were 115 customers, find
(a) the number of oval tables
(b) the number of round tables
Oval tables |
Number of customers around oval tables |
Round tables |
Number of customers around round tables |
Total number of customers |
7 |
7 x 5 = 35 |
7 |
7 x 7 = 49 |
35 + 49 = 84 (x) |
8 |
8 x 5 = 40 |
9 |
9 x 7 = 63 |
40 + 63 = 103 (x) |
9 |
9 x 5 = 45 |
10 |
10 x 7 = 70 |
45 + 70 = 115 (✓) |
(a)
Number of oval tables = 9
(b)
Number of round tables = 10
Answer(s): (a) 9; (b) 10