Camillo used the calculations shown to determine how much he would spend on 2,400 oz of jelly.

Question

48 ounces of jelly costs 3 collars and 84 cents. (StartFraction 48 ounces Over 3 dollars and 84 cents EndFraction) (StartFraction question mark ounces Over 1 dollar EndFraction). Unit price = 13 dollars and 79 cents. 13 dollars and 79 cents (2,400) = 33 thousand and 96 dollars.

What is his error?
He placed the decimal point incorrectly when dividing.
He placed the decimal point incorrectly when multiplying.
He wrote the rate incorrectly.
He did not make an error.

Answer 1

To analyze Camillo's calculation and determine his error, let's break down the information given.

1. Cost of Jelly:

   • 48 ounces cost $3.84 (which is 3 dollars and 84 cents).

2. Calculating the Unit Price:

   • First, we find the unit price of jelly per ounce.
   • \[ \text{Unit price} = \frac{3.84 \text{ dollars}}{48 \text{ ounces}} = \frac{384 \text{ cents}}{48 \text{ ounces}} = 8 \text{ cents per ounce} \] (since \(3.84 \times 100 = 384\)).

3. Calculating Cost for 2,400 Ounces:

   • We now calculate the total cost for 2,400 ounces.
   • \[ \text{Total cost} = 2,400 \text{ ounces} \times 0.08 \text{ dollars per ounce} = 192 \text{ dollars} \]

4. Camillo's Calculation of 33,096 dollars:

   • He claims that the calculation results in 33,096 dollars, which is clearly incorrect based on our calculation.

Identifying the Error:

• The largest discrepancy comes from the claim that the unit price is $13.79 for jelly; this is incorrect. The actual unit price is 8 cents or $0.08 per ounce.

• Thus, it seems that he wrote the rate incorrectly.

Conclusion:

The correct choice is:

He wrote the rate incorrectly.