Question

Mickey used these calculations to find how much he would spend on 7 cartons of eggs, if 12 cartons of eggs cost $22.20. Describe his error.
12 cartons(÷22.20)
$22.22(÷22.20)


Unit price = $0.54
$0.54(7) = $3.78

Answer 1

Mickey incorrectly calculated the unit price:
$\frac{12}{22.20} = 0.54$

The correct operation is:
$\frac{22.20}{12} = 1.85$

Each carton costs 1.85, so 7 cartons cost
$1.85 \times 7 = 12.95$

Answer 2

Answer: Amount spent on 7 cartons of eggs is $12.95.

Step-by-step explanation:

Since we have given that

Number of cartons of eggs = 12

Cost of 12 cartons of eggs = $22.20

So, Unit price of carton of eggs would be

$\dfrac{22.20}{12}\\\\=\ 1.85$

Now, number of cartons of eggs = 7

Amount spent on 7 cartons of eggs is given by

$1.85\times 7\\\\=\ 12.95$

So, 12 cartons(÷22.20), there is a mistake as it should be 22.20÷12.

Hence, Amount spent on 7 cartons of eggs is $12.95.