Some stickers are packed into exactly packets of 6.
If the stickers are repacked into packets of 13,
there are 4 less packets and 3 stickers extra.
- How many packets are there?
- How many stickers are there?
|
Packets of 6 |
Packets of 13 |
Number |
1 u |
1 u - 4 |
Value |
6 |
13 |
Total value |
6 u |
13 u - 49 |
(a)
Let the number of packets of 6 be 1 u.
Number of stickers if they are in packets of 6
= 1 u x 6
= 6 u
Number of stickers if they are in packets of 13
= 13(1 u - 4) + 3
= 13 u - 52 + 3
= 13 u - 49
6 u = 13 u - 49
13 u - 6 u = 49
7 u = 49
1 u = 49 ÷ 7 = 7
Number of packets of 6
= 1 u
= 7
(b)
Number of stickers
= 6 u
= 6 x 7
= 42
Answer(s): (a) 7; (b) 42