Some stickers are packed into exactly packets of 8.
If the stickers are repacked into packets of 15,
there are 3 less packets and needs 5 more stickers to make another packet.
- How many packets are there?
- How many stickers are there?
|
Packets of 8 |
Packets of 15 |
Number |
1 u |
1 u - 3 |
Value |
8 |
15 |
Total value |
8 u |
15 u - 35 |
(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
= 15 - 5
= 10
Number of stickers if they are in packets of 15
= 15(1 u - 3) + 10
= 15 u - 45 + 10
= 15 u - 35
8 u = 15 u - 35
15 u - 8 u = 35
7 u = 35
1 u = 35 ÷ 7 = 5
Number of packets of 8
= 1 u
= 5
(b)
Number of stickers
= 8 u
= 8 x 5
= 40
Answer(s): (a) 5; (b) 40