Solve this problem using an equation of ratios.
3 1/6 yards of the fabric she wants in stock. But this quantity of fabric can make only 1 1/3 shirts
Write the ratio
3 1/6 yards to 1 1/3 shirts:
19
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6
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4
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3
We need to reduce this. The first (upper) ratio is 19/6; the second (lower() ratio is 4/3. We can mult. numerator and denom. of 4/3 both by 2 to obtain the equivalent ratio 8/6.
Then we have the ratio
19/6
-------- which can be reduced to 19/8. That's (19/8) yard/shirt. We can use
8/6 this as a conversion factor.
To make 2 shirts, Mary will need (19/8 yards per shirt)(2 shirts) of material, or 38/8 yards, or 19/4 yards (answer).