Answer: 11/12
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Explanation:
3/4 = 9/12 after multiplying top and bottom by 3
1/3 = 4/12 after multiplying top and bottom by 4
When combining the fractions 3/4 and 1/3, we get,
3/4 + 1/3 = 9/12 + 4/12 = (9+4)/12 = 13/12
Let's convert that result into a mixed number
13/12 = (12+1)/12
13/12 = 12/12 + 1/12
13/12 = 1 + 1/12
13/12 = 1 & 1/12
Adam and Brian have collectively eaten 1 full pizza plus an additional 1/12 of the second pizza. This leaves 11/12 of the second pizza for Christine to eat. Notice how the fractions part 1/12 and 11/12 add to 12/12 = 1.
Check out the diagram below.
