<h3>
Answer: 72 people total</h3>
45 boys, 27 girls
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Explanation:
g = number of girls
g+18 = number of boys, since there are 18 more boys than girls
For example, if g = 7, then g+18 = 7+18 = 25. In this example, we have 7 girls and 25 boys. The problem with this example is the ratio of boys to girls is 25:7 which is not equal to 5:3
We could use trial and error until we land on the solution, or we can use algebra as shown in the next section.
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The ratio of boys to girls is 5:3, meaning
(number of boys)/(number of girls) = 5/3
which turns into
(g+18)/g = 5/3
after we make the proper substitutions
Let's solve for g
(g+18)/g = 5/3
3(g+18) = 5g
3g+54 = 5g
54 = 5g-3g
54 = 2g
2g = 54
g = 54/2
g = 27
There are 27 girls.
This leads to,
g+18 = 27+18 = 45
So there are 45 boys
In total, we have 27+45 = 72 people
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Checking the answer:
The claim is that 45/27 is the same as 5/3
For now assume that claim is true. Set the fractions equal to each other and use cross multiplication like so
45/27 = 5/3
45*3 = 27*5
135 = 135
The third equation has the same thing on both sides, so it's a true equation. This must mean the first equation is true as well. Therefore, 45:27 and 5:3 are the same ratio and the answer is confirmed.
You could also use your calculator to note that
45/27 = 1.667
5/3 = 1.667
both decimal values are approximate.
