2005 AMC 8 Problems/Problem 11
Problem
The sales tax rate in Rubenenkoville is 6%. During a sale at the Bergville Coat Closet, the price of a coat is discounted 20% from its $90.00 price. Two clerks, Jack and Jill, calculate the bill independently. Jack rings up $90.00 and adds 6% sales tax, then subtracts 20% from this total. Jill rings up $90.00, subtracts 20% of the price, then adds 6% of the discounted price for sales tax. What is Jack's total minus Jill's total?
Solution
The price Jack rings up is . The price Jill rings up is . By the commutative property of multiplication, these quantities are the same, and the difference is .
Reminder: Commutative states abc = bac= acb =..... and is the same in any order. This only works for addition and multiplication.
See Also
2005 AMC 8 (Problems • Answer Key • Resources) | ||
Preceded by Problem 10 |
Followed by Problem 12 | |
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All AJHSME/AMC 8 Problems and Solutions |
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