20 students share some stickers.
Each girl gets 2 stickers.
Each boy gets 3 stickers.
In total, the girls get 20 less stickers than the boys.
- How many girls are there?
- How many boys are there?
- How many stickers do the boys get?
- How many stickers do the students get?
Number of boys |
Total stickers that the boys get |
Number of girls |
Total stickers that the girls get |
Less stickers for the girls than the boys |
20
|
20 x 3 = 60 |
0
|
0 x 2 = 0 |
60 - 0 = 60 |
19
|
19 x 3 = 57 |
1
|
1 x 2 = 2 |
57 - 2 = 55 |
12
|
12 x 3 = 36 |
8
|
8 x 2 = 16 |
36 - 16 = 20 |
(a)
Total number of stickers that the students will get if all the students are boys
= 20 x 3
= 60
Total number of less stickers for the girls than the boys if one boy is replaced by a girl
= 19 x 3 - 1 x 2
= 57 - 2
= 55
Big difference in the decrease in the number of stickers when a boy is replaced by a girl
= 60 - 20
= 40
Small difference in the decrease in the number of stickers when a boy is replaced by a girl
= 2 + 3
= 5
Number of girls
= 40 ÷ 5
= 8
(b)
Number of boys
= 20 - 8
= 12
(c)
Number of stickers that the boys get
= 12 x 3
= 36
(d)
Number of stickers that the girls get
= 8 x 2
= 16
Total number of stickers
= 36 + 16
= 52
Answer(s): (a) 8; (b) 12; (c) 36; (d) 52