### Math Notes

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#### High School Mathematics Solutions

##### Topics || Problems

In a class, the ratio of the number of girls to boys is 5:4. If only 15 more girls had enrolled in the class, the ratio would have been 25:8. How many girls are in the class?

• Ratio of Girls(G) to Boys(B): $$5:4 = G:B$$
• $$\frac{5}{4} = \frac{G}{B}$$
• B = 0.8G
• If there are 15 more girls: $$25:8 = G+15:B$$
• $$\frac{25}{8} = \frac{15+G}{B}$$
• $$\frac{25}{8} = \frac{15+G}{0.8G}$$
• $$2.5G = {15+G}$$
• $$G = 10$$
• $$B = 0.8(10) = 8$$

• Total Students = 10 + 8 = 18