PSLEThere were a total of 112 tables and chairs in a basketball court. There were 3 times as many chairs as tables. After 12 chairs and some tables were thrown away, there were 4 times as many chairs as tables left. How many tables were thrown away from the basketball court?
|
Tables |
Chairs |
Total |
Before |
1 u |
3 u |
112 |
Change |
- ? |
- 12 |
|
After |
1 p |
4 p |
|
Number of tables and chairs at first
= 3 u + 1 u
= 112
4 u = 112
1 u = 112 ÷ 4 = 28
Number of chairs at first
= 3 u
= 3 x 28
= 84
Number of chairs left
= 84 - 12
= 72
4 p = 72
1 p = 72 ÷ 4 = 18
Number of tables thrown away from the basketball court
= 28 - 18
= 10
Answer(s): 10