In the seminar room, chairs were arranged in rows of 10. During a workshop, 20 chairs were added to accommodate the number of people. The chairs were rearranged to form rows of 8. 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 |
10 |
8 |
Total value |
10 u |
8 u + 48 |
(a)
Number of chairs in the extra 6 rows
= 6 x 8
= 48
(b)
Total number of chairs in the first arrangement
= 1 u x 10
= 10 u
Total number of chairs in the second arrangement
= 8(1 u + 6)
= 8 u + 48
If 20 chairs were included in the first arrangement, the total number of chairs in the first arrangement and the second arrangement will be the same.
10 u + 20 = 8 u + 48
10 u - 8 u = 48 - 20
2 u = 28
1 u = 28 ÷ 2 = 14
Number of chairs in the seminar room in the end
= 14 x 10 + 20
= 140 + 20
= 160
Answer(s): (a) 48; (b) 160