Some stickers are packed into exactly packets of 15.
If the stickers are repacked into packets of 8,
there are 7 more packets.
- How many packets of 8 are there?
- How many stickers are there?
|
Packets of 15 |
Packets of 8 |
Number |
1 u |
1 u + 7 |
Value |
15 |
8 |
Total value |
15 u |
8 u + 56 |
(a)
Let the number of packets of 15 be 1 u.
Number of stickers if they are in packets of 15
= 15 x 1 u
= 15 u
Number of stickers if they are in packets of 8
= 8 x (1 u + 7)
= 8 u + 56
8 u + 56 = 15 u
15 u - 8 u = 56
7 u = 56
1 u = 56 ÷ 7 = 8
Number of packets of 8
= 1 u + 7
= 8 + 7
= 15
(b)
Number of stickers
= 15 u
= 15 x 8
= 120
Answer(s): (a) 15; (b) 120