PSLEThere were a total of 117 tables and benches in a hall. There were 2 times as many benches as tables. After 18 benches and some tables were removed, there were 4 times as many benches as tables left. How many tables were removed from the hall?
|
Tables |
Benches |
Total |
Before |
1 u |
2 u |
117 |
Change |
- ? |
- 18 |
|
After |
1 p |
4 p |
|
Total number of tables and benches
= 2 u + 1 u
= 3 u
3 u = 117
1 u = 117 ÷ 3 = 39
Number of benches at first
= 2 u
= 2 x 39
= 78
Number of benches left
= 78 - 18
= 60
4 p = 60
1 p = 60 ÷ 4 = 15
Number of tables removed from the hall
= 39 - 15
= 24
Answer(s): 24