Hey there!
For the beginning of the problem, I believe you meant to type "2 3/4" instead of "23/4". But to solve this, you can subtract the numbers 2 3/4 and 1/2 . . .
3/4 - 1/2 . . .
3/4 = 3/4
1/2 = 2/4
3 - 2 = 1
The denominator stays the same, so that leads you to the fraction 1/4 . . .
2 + 1/4 = 2 1/4.
2 3/4 - 1/2 = 2 1/4
You need 2 1/4 quarts of more broth to make the soup.
Hope this helps you.
Have a great day!
