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 Question from Kelly, a student: Rahsad pays $6.30 tax for a pair of shoes that is priced at$45. His friend Zoe purchases another pair of shoes on sale for $25 in the same store. How much tax does Zoe have to pay? Solve the problem in two ways. Show your work. What assumptions did you make? Hi Kelly, One way to approach at this problem is from ratios. If the ratio of the tax paid to the price is the same for both items and$x is the tax on the $25 shoes then$6.30/$45 =$x/$25. Solve for x. Penny On May 12, 2008 we received the following from George I solved the problem as follows Solution: If the ratio of the tax paid to the price is the same for both items and$x is the tax on the $25 shoes then$6.30:$45 =$x:\$25.

Solve for x
First we must make both sides of the equation equal so

Find the common denominator for 45 and 25 = 45*25 = 1125

Both sides of the equation are now equal
? :1125 = ? :1125

To find the value of ?, divide 1125 by 45 to get 25 and multiply 6.30 by 25 to get 157.50

The equation now looks like
157.50:1125 = 157.50:1125

To find the value of x, divide both figures on the right side of the equation by 45 to get 3.5:25
so x=3.5

Would you agree with my solution?

Thanks

George

George,