There are 700 Cal in ¼ lb margarine.
Dietitians say there are anywhere from 150 Cal to 200 Cal in an ounce of margarine.
Let’s split the difference and assume 175 Cal/oz.
a. Given: pounds of margarine
b. Want: number of calories
c. Equalities: 175 Cal = 1 oz; 16 oz = 1 lb
d. Conversion factors: 175 Cal/1 oz or 1 oz/175 Cal; 16 oz = 1 lb or 1 lb/16 oz
We choose the conversion factor that has the desired units on top.
Calculation:
No. of ounces = 0.25 lb × (16 oz/1 lb) = 4 oz
No. of Calories = 4 oz × (175 Cal/1 oz) = 700 Cal
