A pound is approximately 0.45 kilogram. A person weighs 87 kilograms. What is the person’s weight, in pounds, when rounded to the nearest whole number?
The correct answer and explanation is:
To convert kilograms to pounds, you can use the conversion factor where 1 kilogram is approximately equal to 2.2 pounds. To find the weight in pounds of a person who weighs 87 kilograms, multiply the weight in kilograms by the conversion factor.
Here is the calculation: 87 kg×2.2 pounds/kg=191.4 pounds87 \, \text{kg} \times 2.2 \, \text{pounds/kg} = 191.4 \, \text{pounds}
Now, rounding 191.4 to the nearest whole number gives: 191 pounds191 \, \text{pounds}
Thus, a person who weighs 87 kilograms weighs approximately 191 pounds when rounded to the nearest whole number.
Explanation:
- Conversion Factor: The key to solving this problem is knowing the conversion factor between kilograms and pounds. In this case, we use 2.2 pounds per kilogram as the standard conversion factor. This is because, in many contexts, such as weight and mass measurement, this is the approximation commonly used to simplify calculations.
- Multiplication for Conversion: To convert 87 kilograms to pounds, multiply the number of kilograms by the conversion factor. This step is straightforward since it’s simply a multiplication of 87 by 2.2.
- Rounding: After performing the multiplication, the result is 191.4. Since the problem asks for the answer to be rounded to the nearest whole number, we round 191.4 down to 191, because the decimal part (0.4) is less than 0.5.
This process is a simple application of a unit conversion formula combined with rounding techniques. It’s essential to remember that the exact conversion factor can vary slightly depending on the context, but 2.2 pounds per kilogram is a good approximation for everyday use.