Answer: B. $7.76
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Step-by-step explanation:
Ignore the info about how much Margo spent.
Anthony spent $10.24 on lunch, before the tip. Then we add on the $2 tip to get a total of 12.24 dollars spent.
The amount of change is 20-12.24 = 7.76
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Here's how the cashier can mentally figure out how much change to give
Start with the number of cents from $12.24
The jump from 24 cents to 100 cents is 76 cents (24+76 = 100)
This gets us from 12.24 to 13.00
The jump from 13 to 20 is another 7 dollars.
So that's how we get 7 + 0.76 = 7.76 in change