Answer: 5 bars for $4.00 is the better deal
Step-by-step explanation:
The first ratio is
12 bars : 10 dollars
Divide each part of that ratio by 12 so that "12 bars" turns into "1 bar"
12 bars: 10 dollars
(12/12) bars: 10/12 dollars
1 bar: 0.83 dollars
1 bar: 83 cents
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Repeat for the other ratio as shown below. This time we divide both parts by 5 to turn the "5 bars" into "1 bar"
5 bars : 4 dollars
(5/5) bars : 4/5 dollars
1 bar : 0.80 dollars
1 bar : 80 cents
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Deal #1 costs 83 cents per bar. Deal #2 is 80 cents per bar. So deal #2 is cheaper by 3 cents.
The better deal is "5 bars for 4 dollars"