Everything in a store is 34% off. You also have a coupon for an additional 20% off the price. Pick a starting price and calculate the total price you pay at the register if you first take 34% off, and then take the 20% off. Then calculate the total price you pay at the register if you do the calculation the other way around. Does it matter which way you perform the calculation? Show the work/process to find the answer(s), and then write complete sentences to answer the questions.

The total price I pay at the register is $52.8. It doesn't matter which way I perform the calculation because of the conmutative property of multiplication.

Step-by-step explanation:

You have to pick a starting price, for example let the price be $100

$100 represents the 100%. You have to substract the 34% of $100 to the original price to calculate the price you pay.

The calculation of the % off is the same as multiply the price by the number that represents that percent off.

[tex]$100(\frac{34}{100})= 34[/tex] dollars

$100 - 34$ = 66$

Now you have to calculate the 20% of 66$

[tex]66(\frac{20}{100})=13.2[/tex] dollars

The price you pay is:

$66 - $13.2 = $52.8

If you do the calculation the other way around:

You have to calculate the 20% of $100 and substract that value from $100

[tex]100(\frac{20}{100}) = 20[/tex] dollars

$100 - 20$ = $80

Now, you have to calculate the 34% of $80

[tex]80(\frac{34}{100}) = 27.2[/tex] dollars

$80 - $27.2 = $52.8

Notice that the price you pay can also be calculated as 100% - 34% = 66%. This means that if you have a 34% off, the price you pay is the 66% of the price. (If the discount is 20% you actually pay the 80% of the price)

The price I pay is $52.8