Answer: 6 boys
Explanation:
To find the number of boys in the class, we start by dividing the number of girls (18) by the first number in the ratio (which is 3):
This tells us that there are 6 sets of 3 girls in the class.
Since the ratio of girls to boys is 3:1, we know that for every 3 girls, there is 1 boy. So, for the 6 sets of girls we just found, there must be 6 sets of boys as well:
So, there are 6 boys in the class.
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