Explanation:
All you gotta do is multiply all the test amounts by 5 1/2.
If you have a calculator handy, I would change everything to decimals.
So for chopped onions, you would need
1.5 lbs x 5.5 = 8.25 = 8 1/4 lbs of chopped onion.
Chopped green pepper
.5 lbs x 5.5 = 2.75 = 2 3/4 lbs chopped onion.
Carrots
.5 lbs c 5.5 = 3.75 = 2 3/4 lbs carrots
Chopped Celery
4 stalks x 5.5 = 22 stalks of chopped celery.
And so on. I think you can do it from there.