Betrys needs another 400 grams of diced potatoes to make her vegetable stew for 8 people.
We know that Betrys is cooking for 8 people, and we know that a recipe for 2 people needs 10 ounces.
8 people is 4 times 2 people, then for 8 people you need 4 times 10 ounces, this is 4*10 oz = 40 ounces.
Now we can apply a change of units, remember that:
1 oz = 28 grams
Then the total amount she needs is:
40 oz = 40*28 g = 1,120 g
So she needs in total 1,120 grams, and in the balance, she already has 720 grams, so the amount that she needs is given by the subtraction:
1,120 g - 720g = 400
Betrys needs another 400 grams of diced potatoes to make her vegetable stew for 8 people.
If you want to learn more about subtractions:
https://brainly.com/question/25421984
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