Answer:
Step-by-step explanation:
If we let c and p represent the cups of cheese and plates of nachos, we have ...
c = 2/3p . . . . . each plate of nachos requires 2/3 cups of cheese
Solving for p, we find ...
(3/2)c = p . . . . . multiply by 3/2
Then for 5 cups of cheese, we have ...
(3/2)(5) = p = 15/2 = 7 1/2 . . . . plates of nachos
5 cups of cheese will make 7 full plates of nachos.
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For 9 plates of nachos, we need ...
c = 2/3(9) = 6 . . . . . . cups of cheese
Since we have 5 cups of cheese, we need 1 more cup of cheese to make 9 plates of nachos.