“If 1 kilogram (kg) equals 2.2 pounds (lbs), how many kg are there in 130 lbs? (To the nearest tenth of a kg.) a.286 kg b.62.3 kg c.59.1 kg d.58.7 kg”
The Correct Answer and Explanation is:
To convert pounds (lbs) to kilograms (kg), we can use the given conversion factor: 1 kg = 2.2 lbs. Therefore, to find the number of kilograms in 130 lbs, we will use the formula:
[
\text{Weight in kg} = \frac{\text{Weight in lbs}}{\text{Conversion factor}}
]
In this case, we will substitute the known values into the equation:
[
\text{Weight in kg} = \frac{130 \text{ lbs}}{2.2 \text{ lbs/kg}}
]
Calculating this gives:
[
\text{Weight in kg} = \frac{130}{2.2} \approx 59.0909
]
When rounded to the nearest tenth, this value becomes 59.1 kg.
Detailed Explanation
- Understanding the Conversion: The relationship between kilograms and pounds is established through a conversion factor. Knowing that 1 kg is approximately 2.2 lbs, we can find the equivalent weight in kilograms for any given weight in pounds by dividing the number of pounds by 2.2.
- Setting Up the Calculation: The calculation requires dividing the total pounds (130 lbs) by the conversion factor (2.2 lbs/kg). This approach allows us to convert from a larger unit (pounds) to a smaller unit (kilograms).
- Performing the Calculation: When we divide 130 by 2.2, we perform the arithmetic operation, which gives us approximately 59.0909 kg.
- Rounding the Result: The problem specifies to round to the nearest tenth of a kilogram. In this case, since the first decimal place after 59.0 is a zero, we simply retain the value as 59.1 kg.
- Conclusion: The final result indicates that 130 lbs is equivalent to approximately 59.1 kg when converted using the specified conversion factor. This approach is essential in various practical applications, including weight management, nutrition, and fitness, where conversions between metric and imperial units are often necessary.
Therefore, the correct answer is c. 59.1 kg.