Question

3. A clothing store is having a sale with all clothes being 10% - 30% off the original retail price.

(CAREFUL)
What would be the possible prices for a shirt with an original price of $60?

Answer 1

Answer: between $42 and $54 including both endpoints.

In symbolic form we can say
`42 \le p \le 54` where p is the final price after the discount is applied.

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Step-by-step explanation:

10% off means you save 10% but pay the remaining 90%

Then convert 90% to decimal form to get 0.90

If the original price is $60, then the final price is 0.90*60 = 54 dollars.

In other words,

10% of 60 = 0.10*60 = 6 dollars saved

60-6 = 54 is the final price

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If the discount is 30% then you pay the remaining 70%

0.70*60 = 42

Or you can think of it like this

30% of 60 = 0.30*60 = 18 dollars saved

60-18 = 42 dollars is the final price

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Let's summarize with this chart:

`\begin{array} \cline{1-3}\text{Discount} & \text{Amount Saved} & \text{Final Price}\\\cline{1-3}10\% & \$6 & \$54\\\cline{1-3}30\% & \$18 & \$42\\\cline{1-3}\end{array}`

Therefore, the final price after the discount is between $42 and $54 including both endpoints.

Side note: The jump from 10% to 30% is "times 3"; so is the jump from $6 to $18 in the "amount saved" column of the table.