In the seminar room, chairs were arranged in rows of 17. During a workshop, 35 chairs were added to accommodate the number of people. The chairs were rearranged to form rows of 12. As a result, there were 5 more rows.
- How many chairs were there in the extra 5 rows?
- How many chairs were there in the seminar room in the end?
|
First arrangement |
Second arrangement |
Number |
1 u |
1 u + 5 |
Value |
17 |
12 |
Total value |
17 u |
12 u + 60 |
(a)
Number of chairs in the extra 5 rows
= 5 x 12
= 60
(b)
Total number of chairs in the first arrangement
= 1 u x 17
= 17 u
Total number of chairs in the second arrangement
= 12(1 u + 5)
= 12 u + 60
If 35 chairs were included in the first arrangement, the total number of chairs in the first arrangement and the second arrangement will be the same.
17 u + 35 = 12 u + 60
17 u - 12 u = 60 - 35
5 u = 25
1 u = 25 ÷ 5 = 5
Number of chairs in the seminar room in the end
= 5 x 17 + 35
= 85 + 35
= 120
Answer(s): (a) 60; (b) 120