Answer:
5:3
Explanation:
You want the ratio of boys to girls, given the proportion of boys is 5/8.
Ratio
The remaining 1 -5/8 = 3/8 of the school is girls. Then the ratio of boys to girls is ...
boys : girls = 5/8 : 3/8 = 5 : 3
The ratio of boys to girls is 5:3.
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Additional comment
All parts of a ratio can be multiplied by the same number without changing the ratio. Here, we multiplied by 8 to eliminate the fractions.