Oh, dude, it's like adding fractions at a math party. So, one and two thirds plus one and two thirds equals... drumroll... four! Yep, that's right, four! So, if you've got one Pizza with two-thirds eaten, and your friend brings another pizza with two-thirds eaten, you've got a full pizza party with four-thirds of pizza left!
4 and two thirds 4 and two thirds
One third plus one third equals two thirds.
15 and two thirds plus four fifths = one two fiftenth
thiry three and one third
11/12 is the answer.