In a school, 0.9 of the girls and 0.7 of the boys take part in charity work. There is an equal number of boys and girls who do not take part in charity work. If 42 students do not take part in charity work, how many more students take part in charity work than those who do not take part in charity work?
Girls |
Boys |
Take part |
Do not take part |
Take part |
Do not take part |
9x3 |
1x3 |
7 |
3 |
|
1x3 |
|
1x3 |
27 u |
3 u |
7 u |
3 u |
0.9 =
910 Girls that take part : Girls that do not take part = 9 : 1
0.7 =
710 Boys that take part : Boys that do not take part = 7 : 3
The number of boys who do not take part is repeated. Make the number of boys who do not take part the same. LCM of 1 and 3 is 3.
Number of students who do not take part in charity work
= 3 u + 3 u
= 6 u
6 u = 42
1 u = 42 ÷ 6 = 7
Number of students who take part in charity work
= 27 u + 7 u
= 34 u
Number of more students who take part in charity work than those who do not take part in charity work
= 34 u - 6 u
= 28 u
= 28 x 7
= 196
Answer(s): 196