PSLEIn a school hall, chairs were arranged in rows such that there were exactly 29 chairs in each row. For a concert, Daniel brought 4 more chairs into the school hall and rearranged all the chairs. There are now exactly 8 chairs in each row and 11 more rows than before. How many chairs are there in the school hall for the concert in the end?
|
Before |
After |
Number |
1 u |
1 u + 11 |
Value |
29 |
8 |
Total value |
29 u + 4 |
8 u + 88 |
Number of rows at first = 1 u
Number of rows in the end = 1 u + 11
Number of chairs at first after the 4 chairs were brought in
= 29 x 1 u + 4
= 29 u + 4
Number of chairs in the end
= 8 x (1 u + 11)
= 8 u + 88
The total number of chairs is equal.
29 u + 4 = 8 u + 88
29 u - 8 u = 88 - 4
21 u = 84
1 u = 84 ÷ 21 = 4
Number of chairs in the end
= 8 u + 88
= 8 x 4 + 88
= 120
Answer(s): 120