Carrots are $0.79 per pound. What is the cost of 1.20 kg of carrots?
A) $2.10
B) $0.43
C) $1.45
D) $0.79
E) $0.95
The correct answer and explanation is :
To determine the cost of 1.20 kg of carrots when the price is $0.79 per pound, we need to convert kilograms to pounds, since the price is given per pound.
Step 1: Convert kilograms to pounds
We use the conversion factor:
1 kilogram = 2.20462 pounds
So:
1.20 kg × 2.20462 lb/kg = 2.645544 lb
Now we know that 1.20 kg of carrots equals approximately 2.6455 pounds.
Step 2: Multiply by the cost per pound
The price is $0.79 per pound. So:
2.6455 lb × $0.79/lb = $2.089945
Rounding to the nearest cent:
$2.09 (approximately)
But looking at the answer options, we see:
- A) $2.10
- B) $0.43
- C) $1.45
- D) $0.79
- E) $0.95
The closest and most accurate answer is:
A) $2.10
Explanation
This type of problem is a common real-world math application involving unit conversions and multiplication. The key here is recognizing that the cost is given per pound, but the quantity is given in kilograms, which means a unit conversion is necessary before multiplying.
To avoid errors:
- Always identify the unit mismatch first (kg vs lb).
- Use the correct conversion factor: 1 kg = 2.20462 lb.
- Multiply the converted weight by the cost per pound.
- Round the result to the nearest cent if dealing with money.
Many mistakes in such problems arise from either skipping the unit conversion or using an incorrect conversion factor. Practicing these steps ensures accuracy in similar everyday scenarios, like grocery shopping or interpreting product labels.