Question

JustMaths Q1. The ratio of the number of boys to girls at a party is 3:4 Six boys leave the party. The ratio of the number of boys to girls at the party is now 5:8 work out the number of girls at the party.

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Answer 1

To calculate the number of girls at the party, set up a proportion using the initial and new ratios of boys to girls. The number of girls is approximately 6.7.

Step-by-step explanation:

To calculate the number of girls at the party, we need to understand the change in ratio when six boys leave.

Let's start with the initial ratio of boys to girls, which is 3:4. This means that for every 3 boys, there are 4 girls.

When six boys leave, the new ratio becomes 5:8. This means that for every 5 boys, there are 8 girls.

We can set up a proportion to solve for the number of girls. We have 3 boys to 4 girls initially and 5 boys to x girls after six boys leave. This gives us the equation:

3/4 = 5/x

Cross-multiplying, we get:

3x = 20

Dividing both sides by 3, we find:

x = 20/3

So, the number of girls at the party is approximately 6.7.