Zakiyyah M. answered • 02/28/14

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Zakiyyah

Lisa G.

asked • 02/27/14have been setting up word problems as proportions but i cant seem to get this one right.

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Zakiyyah M. answered • 02/28/14

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Here is another approach with a lot of detail.

Let x = cost of the room before taxes (since this is what we want to find, let it be x. This is good practice for all word problems)

9% tax is equivalent to .09 (removing the percent sign and replacing with 9/100 because 9% = 9/100)

$tax = .09x

68 it total cost of the room plus total tax simply put:

$68 = $room + $tax (note that tax in this equation is the dollar amount, not the percentage of tax)

So that means

x+ (.09x) = 68 or ( × + (9/100)x = 68)

1x+ .09x = 68

1.09x = 68 (divide both sides by 1.09)

x = 68/1.09

x = 62.385 (round to the nearest 100th because it's money. Money only goes out 2 decimal places. So round UP because the last number is 5)

x = $62.39 FINAL ANSWER

check your work:

$tax = 62.39*.09 = 5.62

$room + $tax = $68

$62.39 + $5.62 = 68.01 (close enough.. because of rounding it's a little off... but still correct)

The reason Bam's answer is wrong is because the 9% is based off of the cost of the room BEFORE taxes. This is a common mistake in calculating taxes. Always remember that taxes are based off the ORIGINAL cost, not final.

Hope that helps.

Zakiyyah

Parviz F. answered • 02/27/14

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C - Cost of Hotel r = Tax rate

C + C r = C ( 1 +r)

C (1 + 0.09 ) = $68

C = $68/1.09 = $62.39

Bam K. answered • 02/27/14

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room and tax minus tax = room before tax

$68 - 9% of $68 is the cost of the room before tax : that is $68 x (1 - 0.09) = $68 x (0.91) = $61.88

ATTENTION! PARVIZ'S ANSWER IS NOT CORRECT!

Zakiyyah M.

This answer is incorrect.

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02/28/14

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Parviz F.

02/28/14