Some stickers are packed into exactly packets of 8.
If the stickers are repacked into packets of 20,
there are 2 less packets and needs 4 more stickers to make another packet.
- How many packets are there?
- How many stickers are there?
|
Packets of 8 |
Packets of 20 |
Number |
1 u |
1 u - 2 |
Value |
8 |
20 |
Total value |
8 u |
20 u - 24 |
(a)
Let the number of packets of 8 be 1 u.
Number of stickers if they are in packets of 8
= 1 u x 8
= 8 u
Number of stickers left if another packet is not packed
= 20 - 4
= 16
Number of stickers if they are in packets of 20
= 20(1 u - 2) + 16
= 20 u - 40 + 16
= 20 u - 24
8 u = 20 u - 24
20 u - 8 u = 24
12 u = 24
1 u = 24 ÷ 12 = 2
Number of packets of 8
= 1 u
= 2
(b)
Number of stickers
= 8 u
= 8 x 2
= 16
Answer(s): (a) 2; (b) 16