20 students share some stickers.
Each girl gets 2 stickers.
Each boy gets 3 stickers.
In total, the girls get 20 more stickers than the boys.
- How many boys are there?
- How many girls are there?
- How many stickers do the boys get?
- How many stickers do the children get?
Number of girls |
Total stickers that the girls get |
Number of boys |
Total stickers that the boys get |
More stickers for the girls than the boys |
20 |
20 x 2 = 40 |
0 |
0 x 3 = 0 |
40 - 0 = 40 |
19 |
19 x 2 = 38 |
1 |
1 x 3 = 3 |
38 - 3 = 35 |
16 |
16 x 2 = 32 |
4 |
4 x 3 = 12 |
32 - 12 = 20 |
(a)
Number of more stickers for the girls than the boys if all the students are girls,
= 20 x 2
= 40
Number of more stickers for the girls than the boys if one girl is replaced by a boy
= 19 x 2 - 1 x 3
= 38 - 3
= 35
Big difference in the decrease in the number of stickers when a girl is replaced by a boy
= 40 - 20
= 20
Small difference in the decrease in the number of stickers when a girl is replaced by a boy
= 2 + 3
= 5
Number of boys
= 20 ÷ 5
= 4
(b)
Number of girls
= 20 - 4
= 16
(c)
Number of stickers that the boys get
= 4 x 3
= 12
(d)
Number of stickers that the girls get
= 16 x 2
= 32
Total number of stickers
= 12 + 32
= 44
Answer(s): (a) 4; (b) 16; (c) 12; (d) 44