Some stickers are packed into exactly packets of 15.
If the stickers are repacked into packets of 8,
there are 5 more packets and 2 stickers left.
- How many packets are there?
- How many stickers are there?
|
Packets of 15 |
Packets of 8 |
Number |
1 u |
1 u + 5 |
Value |
15 |
8 |
Total value |
15 u |
8(1 u + 5) + 2 = 8 u + 42 |
(a)
Let the number of packets of 15 be 1 u.
Number of stickers if they are in packets of 15
= 1 u x 15
= 15 u
Number of stickers if they are in packets of 8
= 8 x (1 u + 5) + 2
= 8 u + 40 + 2
= 8 u + 42
15 u = 8 u + 42
15 u - 8 u = 42
7 u = 42
1 u = 42 ÷ 7 = 6
Number of packets of 15
= 1 u
= 6
(b)
Number of stickers
= 15 u
= 15 x 6
= 90
Answer(s): (a) 6; (b) 90