In the seminar room, chairs were arranged in rows of 16. During a workshop, 36 chairs were added to accommodate the number of people. The chairs were rearranged to form rows of 12. As a result, there were 6 more rows.
- How many chairs were there in the extra 6 rows?
- How many chairs were there in the seminar room in the end?
| |
First
arrangement |
Second
arrangement |
| Number |
1 u |
1 u + 6 |
| Value |
16 |
12 |
| Total value |
16 u |
12 u + 72 |
(a)
Number of chairs in the extra 6 rows
= 6 x 12
= 72
(b)
Total number of chairs in the first arrangement
= 1 u x 16
= 16 u
Total number of chairs in the second arrangement
= 12(1 u + 6)
= 12 u + 72
If 36 chairs were included in the first arrangement, the total number of chairs in the first arrangement and the second arrangement will be the same.
16 u + 36 = 12 u + 72
16 u - 12 u = 72 - 36
4 u = 36
1 u = 36 ÷ 4 = 9
Number of chairs in the seminar room in the end
= 9 x 16 + 36
= 144 + 36
= 180
Answer(s): (a) 72; (b) 180
