Marissa worked 7 1/4 hours on Monday. She worked 9 3/4 hours on tuesday, how many hours did she work in all on monday and tuesday, is the answer 15 1/4 hours

No.

7 + 9 is more than 15.

no, that is not the answer.

what is 1/4 + 3/4 ?

then add 7+9

now add both of those results together.

Is the answer 16 4/4 hours

That's right. Now simplify it.

Is the answer 16 1/4 hours

No.

4/4 = 1

Think of a pizza cut into 4 pieces. Each piece is 1/4 of the pizza. 4/4 = 1 whole.

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