Answers:
Ratio of girls to boys is 2:1
Ratio of boys to girls is 1:2
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Step-by-step explanation:
2/3 of the class are girls. If the class had 3 people, then 2 of them are girls. The remaining 3-2 = 1 person is a boy.
The ratio of girls to boys has us list the number of girls (2) followed by the number of boys (1). Separate the values with a colon. That's how we end up with 2:1
The ratio of boys to girls will have us flip that previous ratio to get 1:2
The order is important when it comes to forming ratios.