Some stickers are packed into exactly packets of 7.
If the stickers are repacked into packets of 10,
there are 4 less packets and needs 6 more stickers to make another packet.
- How many packets are there?
- How many stickers are there?
|
Packets of 7 |
Packets of 10 |
Number |
1 u |
1 u - 4 |
Value |
7 |
10 |
Total value |
7 u |
10 u - 36 |
(a)
Let the number of packets of 7 be 1 u.
Number of stickers if they are in packets of 7
= 1 u x 7
= 7 u
Number of stickers left if another packet is not packed
= 10 - 6
= 4
Number of stickers if they are in packets of 10
= 10(1 u - 4) + 4
= 10 u - 40 + 4
= 10 u - 36
7 u = 10 u - 36
10 u - 7 u = 36
3 u = 36
1 u = 36 ÷ 3 = 12
Number of packets of 7
= 1 u
= 12
(b)
Number of stickers
= 7 u
= 7 x 12
= 84
Answer(s): (a) 12; (b) 84