math
posted by shelly on .
I know the answer. I don't know how to get to the answer to this problem:
The number of marbles Mari has is 2/3 the number Tanya has. Together they have 40 marbles. How many marbles does Tanya have? I know the answer is 24, but how?

The total number of marbles is 2+3 units, or 5 units.
5 units = 40.
Divide 5 from each side, and get 1 unit = 8.
Tanya has 3 units, so 3 units = 24 Ans. 