Some stickers are packed into exactly packets of 8.
If the stickers are repacked into packets of 18,
there are 5 less packets.
- How many packets are there?
- How many stickers are there?
|
Packets of 8 |
Packets of 18 |
Number |
1 u |
1 u - 5 |
Value |
8 |
18 |
Total value |
8 u |
18(1 u - 5) = 18 u - 90 |
(a)
Let the number of packets of 8 be 1 u.
Number of stickers in packets of 8
= 1 u x 8
= 8 u
Number of stickers in packets of 18
= 18 x (1 u - 5)
= 18 u - 90
8 u = 18 u - 90
18 u - 8 u = 90
10 u = 90
1 u = 90 ÷ 10 = 9
Number of packets of 8 = 9
(b)
Number of stickers
= 8 u
= 8 x 9
= 72
Answer(s): (a) 9; (b) 72