15 students share some stickers.
Each boy gets 3 stickers.
Each girl gets 4 stickers.
In total, the boys get 39 less stickers than the girls.
- How many boys are there?
- How many girls are there?
- How many stickers do the girls get?
- How many stickers do the students get?
Number of girls |
Total stickers that the girls get |
Number of boys |
Total stickers that the boys get |
Less stickers for the boys than the girls |
15
|
15 x 4 = 60 |
0
|
0 x 3 = 0 |
60 - 0 = 60 |
14
|
14 x 4 = 56 |
1
|
1 x 3 = 3 |
56 - 3 = 53 |
12
|
12 x 4 = 48 |
3
|
3 x 3 = 9 |
48 - 9 = 39 |
(a)
Total number of stickers that the students will get if all the students are girls
= 15 x 4
= 60
Total number of less stickers for the boys than the girls if one girl is replaced by a boy
= 14 x 4 - 1 x 3
= 56 - 3
= 53
Big difference in the decrease in the number of stickers when a girl is replaced by a boy
= 60 - 39
= 21
Small difference in the decrease in the number of stickers when a girl is replaced by a boy
= 3 + 4
= 7
Number of boys
= 21 ÷ 7
= 3
(b)
Number of girls
= 15 - 3
= 12
(c)
Number of stickers that the girls get
= 12 x 4
= 48
(d)
Number of stickers that the boys get
= 3 x 3
= 9
Total number of stickers
= 48 + 9
= 57
Answer(s): (a) 3; (b) 12; (c) 48; (d) 57