Some stickers are packed into exactly packets of 6.
If the stickers are repacked into packets of 15,
there are 3 less packets.
- How many packets are there?
- How many stickers are there?
|
Packets of 6 |
Packets of 15 |
Number |
1 u |
1 u - 3 |
Value |
6 |
15 |
Total value |
6 u |
15(1 u - 3) = 15 u - 45 |
(a)
Let the number of packets of 6 be 1 u.
Number of stickers in packets of 6
= 1 u x 6
= 6 u
Number of stickers in packets of 15
= 15 x (1 u - 3)
= 15 u - 45
6 u = 15 u - 45
15 u - 6 u = 45
9 u = 45
1 u = 45 ÷ 9 = 5
Number of packets of 6 = 5
(b)
Number of stickers
= 6 u
= 6 x 5
= 30
Answer(s): (a) 5; (b) 30