Start by multiplying 2/3 by 5.
2 x 5 = 10, so you have 10/3.
This the same as dividing 10 by 3.
3/3 = 1, and 3 goes into 10 3 times, with 1 left over, so 10/3 = 3, 1/3.
2/3 of 5 cups is 3 full cups and 1/3 of a cup.
What is 2/3rds of 5 cups?
Or even simpler, (5/3) x2 3.3333 or 3 1/3