Some stickers are packed into exactly packets of 7.
If the stickers are repacked into packets of 10,
there are 6 less packets and 3 stickers extra.
- How many packets are there?
- How many stickers are there?
|
Packets of 7 |
Packets of 10 |
Number |
1 u |
1 u - 6 |
Value |
7 |
10 |
Total value |
7 u |
10 u - 57 |
(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 if they are in packets of 10
= 10(1 u - 6) + 3
= 10 u - 60 + 3
= 10 u - 57
7 u = 10 u - 57
10 u - 7 u = 57
3 u = 57
1 u = 57 ÷ 3 = 19
Number of packets of 7
= 1 u
= 19
(b)
Number of stickers
= 7 u
= 7 x 19
= 133
Answer(s): (a) 19; (b) 133