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Algebra Difficulty 2.5 Junior Find the answer Canada

In a school fundraising campaign, 25% of the money donated came from parents. The rest of the money was donated by teachers and students. The ratio of the amount of money donated by teachers to the amount donated by students was $2 : 3$ . The ratio of the amount of money donated by parents to the amount donated by students was

Pick one

Solution

Since 25% of the money donated came from parents, then the remaining $100\%-25\% = 75\%$ came from the teachers and students.

Since the ratio of the amount donated by teachers to the amount donated by students is $2:3$ , then the students donated $\frac{3}{2+3}=\frac{3}{5}$ of this remaining 75%.

This means that the students donated $\frac{3}{5}\times 75\% = 45\%$ of the total amount.

Therefore, the ratio of the amount donated by parents to the amount donated by students is $25\% : 45\% = 25: 45 = 5:9$ .

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