Question

the following is a direct proportion and thus a conversion factor: 1.0 g fat = 9.0 cal
true
false

Explanation:

Step1: Define direct proportion

A direct proportion means the ratio between two quantities is constant. Here the ratio of grams of fat to calories is $\frac{9.0\text{ CAL}}{1.0\text{ g}} = 9.0\frac{\text{CAL}}{\text{g}}$, a constant.

Step2: Identify conversion - factor property

A conversion factor is a ratio of equal values used to convert one unit to another. Since $1.0\text{ g}$ of fat is always equal to $9.0\text{ CAL}$, it can be used as a conversion factor.

Answer:

True