There was a total of 41 pupils in a class. Each girl made 35 bookmarks while each boy made 20 bookmarks for a fundraising project. The total number of bookmarks made by all the pupils was 1165. How many girls were there in the class?
Supposed there were 41 boys in the class,
41 × 20 = 820
(short of) 1165 - 820 = 345
(difference) 35 - 20 = 15
No. of girls in the class
= 345 ÷ 15
= 23
23 girls were in the class.
There was a total of 41 pupils in a class. Each girl made 35 bookmarks while each boy made 20 bookmarks for a fundraising project. The total number of bookmarks made by all the pupils was 1165. How many girls were there in the class?
Let G represent the number of girls
Let B represent the number of boys
G + B = 41 (equation 1)
35G + 20B = 1165 (equation 2)
Multiply eq 1 by 20 20G + 20B = 820 (equation 3)
Subtract eq 3 from eq 2 35G + 20B = 1165
20G + 20B = 820
15G = 345
G = 23 girls
You can substitute 23 into equation 1 to find the number of boys,
but the problem didn't ask for the number of boys.