Answer:
The caterer charged $50 for an adult's meal and $13 for a child's meal
Explanation:
Let the cost of an adult meal be $x
and the cost of a child meal be $y
From the question,
Manny plans to have 66 adults and 27 children and the total cost of his meals is $3,651.
We can write that
66x + 27y = 3651 ...... (1)
Also, from the question,
Zack has 77 adults and 43 children and the total cost he will pay the caterer is $4,409.
We can also write that
77x + 43y = 4409 ...... (2)
Multiply equation (1) by 7, so that we get
462x + 189y = 25557 ...... (3)
Multiply equation (2) by 6, so that
462x + 258y = 26454 ...... (4)
Now, subtract equation (3) from equation (4), so that
69y = 897
∴ y = 897/69
y = 13
Put the value of y into equation (1) to get x
66x + 27y = 3651
∴ 66x + 27(13) = 3651
66x + 351 = 3651
66x = 3651 - 351
66x = 3300
x = 3300/66
x = 50
Therefore,
The cost of an adult's meal is $50
and the cost of a child's meal is $13
Hence, the caterer charged $50 for an adult's meal and $13 for a child's meal.