Question

Explain how to use the unit-factor method to convert 120 pounds to kilogramsTo write the unit factors, use the / symbol, like this: 1 gallon/3.79 liters.

Answer 1

Step-by-step explanation

We know the following relation between pounds (lbs) and kilograms (kg):

`1\text{ }lb=0.4536\text{ }kg\Rightarrow1=\frac{0.4536\text{ }kg}{1\text{ }lb}.`

The unit-factor method consists in multiplying the quantity expressed in pounds by the expression above and then cancelling the lb to obtain the result in kg:

`120\text{ }lb*\frac{0.4536\text{ }kg}{1\text{ }lb}=(120*0.4536)* kg=54.432\text{ }kg.`Answer

120 lb = 54.432 kg