Answer: 4 & 1/6
4 full pizzas plus 1/6 of a pizza
i.e. 4 full pizzas plus one extra slice
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Step-by-step explanation:
1/2 = 3/6
2/3 = 4/6
The fractions add to 1/2 + 2/3 = 3/6 + 4/6 = 7/6 = 1 & 1/6
That first "1" is the carry and it adds to the 3 whole pizzas Dave ate. So we have 3+1 = 4 full pizzas consumed, plus an additional 1/6 of a pizza.
This gives the mixed number 4 & 1/6
Check out the diagram below. I show Dave's slices in blue, and Daisy's slices in pink for the first two rows. The third row is the combination of those slices to get 4 full pizzas and 1 extra slice (to represent that extra 1/6). Let me know if you have questions about the diagram, or the steps in general.