PSLE In a school, 40% of the members in Dancing Club and 45% of the members in Singing Club are boys. Both clubs have the same number of girls. The Singing Club has 20 more boys than the Dancing Club. How many boys are there altogether?
|
Dancing Club |
Singing Club |
Types |
Boys |
Girls |
Boys |
Girls |
Comparing the boys and the girls in each club |
2x11 |
3x11 |
9x3 |
11x3 |
Comparing the girls in 2 clubs |
|
1 |
|
1 |
|
22 u |
33 u |
27 u |
33 u |
40% =
40100 =
25 Fraction of the members in Dancing Club that are girls
= 1 -
25 =
35 45% =
45100 =
920 Fraction of the members in Singing club that are girls
= 1 -
920 =
1120 The number of girls in both clubs is the same. Make the numerators the same. LCM of 3 and 11 is 33.
3x115x11 of the members in Dancing Club =
11x320x3 of the members in Singing Club
3355of the members in Dancing Club =
3360 of the members in Singing Club
Number of more boys in Singing Club than Dancing Club
= 27 u - 22 u
= 5 u
5 u = 20
1 u = 20 ÷ 5 = 4
Total number of boys
= 22 u + 27 u
= 49 u
= 49 x 4
= 196
Answer(s): 196