Answer:
1/4 of the pot is left.
Explanation:
Let x be the total amount of pasta in the pot.
Then the amount of pasta her mother got= 1x/12
The amount of pasta her brother got= 1x/6
The total amount of pasta he serve= 1x/12 + 1x/6
First, convert them into like fractions, then
The total amount of pasta he serve= 1x/12 + 2x/12 = (x+2x)/12 = 3x/12 = 1x/4
Hence, 1/4 of the pot is left over.