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Sneakers at Mr. Lou's garage sale cost the same price. Alexander paid $90.52 for four pairs. How many pairs of sneakers did Justin buy if he paid $135.78? Write a proportion and use cross products to solve for d, the number of sneakers that David bought

User Darken
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1 Answer

6 votes

Answer:

6 pairs

Explanation:

Since we are given a ratio/proportion problem and 3 values and 1 variable then we can use the Rule of three to solve this problem. We simply multiply the diagonal values available and divide by the 3 value to find the variable of the ratio like so...

4 pairs <======> $90.52

d pairs <======> $135.78

(4 * 135.78) / 90.52 = 6 pairs

Finally, we can see that Justin ended up buying a total of 6 pairs of sneakers.

User Rich Von Lehe
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