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primary 6 | Maths
| Percentage
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I dont understand it
If there are 20 more boys than girls in the first group, and 12 more girls than boys in the second group , then
20 - 12 = 8
Overall there are 8 more boys than girls. The difference between their numbers is 8.
Since 45% of participants are girls,
100% - 45% = 55%
55% of participants are boys.
Difference = 55% - 45% = 10%
So 10% →8 people
55% → 8 people x 55/10 = 44
There were 44 boys
Let the number of girls in the first group be 1 unit.
Then number of boys in the first group
= 1 unit + 20
Let the number of boys in the second group be 1 part.
Then number of girls in the second group
= 1 part + 12
Total number of girls = 1 unit + 1 part + 12
Total number of boys = 1 unit + 1 part + 20
Difference = 20 - 12 = 8
So overall there are 8 more boys than girls.
You will get the same result with model drawing. This is just the word equivalent of model drawing
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