For every 3 chocolates that Claire buys at the regular price, she buys a fourth chocolate for 25 cents. Claire buys 12 chocolates in total for $6.15. What is the regular price of one chocolate, in cents?
, 2013
Pick one
Solution
For every 3 chocolates that Claire buys at the regular price, she buys a fourth for 25 cents.
Consider dividing the 12 chocolates that Claire buys into 3 groups of 4 chocolates.
In each group of 4, Claire buys 3 chocolates at the regular price and the fourth chocolate is purchased for 25 cents.
That is, of the 12 chocolates that Claire buys, 3 are bought at 25 cents each while the remaining 9 are purchased at the regular price.
The total cost to purchase 3 chocolates at 25 cents each is cents.
Since Claire spent 6.15 and the total cost of the 25 cent chocolates was 75 cents, then the cost of the regular price chocolates was \$6.15-\$0.75=\$5.40$.
Since 9 chocolates were purchased at the regular price for a total of 5.40, then the regular price of one chocolate is or 60 cents.
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