Explanation:
They are 7 ounces of combined meat and cheese in each sandwich (4+3 =7)
There were 13 sandwiches made in the hour (91 oz/7 oz = 13)
52 ounces of meat were used (4*13 = 52) If 13 sandwiches were made, and we know that 4 ounces of meat were used on each sandwich, 4*13 would tell us how many ounces of meat total were used.
39 ounces of cheese were used (3*13 = 39) If 13 sandwiches were made, and we know that 3 ounces of cheese were used on each sandwich, 3*13 would tell us how many ounces of cheese total were used.
You can check to see if the multiplication answers are correct by adding them (39+52 = 91)
I hope this helps you!
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