# Shirt Sale

Alignments to Content Standards: 6.RP.A.3.c

Selina bought a shirt on sale that was 20% less than the original price. The original price was $\$ $5 more than the sale price. What was the original price? Explain or show work. ## IM Commentary There are several different ways to reason through this problem; two approaches are shown. ## Solutions Solution: Tape diagram Solution: A tape diagram (known in some circles as a strip or bar diagram) shows the solution in a very succinct way: Since the difference between the original price and the sale price is$\5, which is also 20% of the original price, the original price is 5 times $\$ $5. The original price was$\25.
We know that 20% of the original price is $\$ $5. Furthermore, 20% of the original price is the same thing as$\frac{20}{100}=\frac15$of the original price. We know that$\frac15$of a quantity is 5, so we can solve this problem by dividing 5 by$\frac15$(this is a Group Size Unknown problem). $$5 \div \frac15 = 25$$ So the original price was$\25.