Question

A mixture contains 1/16 pound sand and 7/8 pound compost. At that rate, what amount of sand is needed if the mixture contains 1 pound of compost?
A.

1/14

pound


B.

8/24

pound


C.

14 pounds


D.

15/16

pound

Answer 1

Answer:

A. ¹/₁₄ lb  

Step-by-step explanation:

¹/₁₆ lb sand goes with ⅞ lb compost.

For 1 lb compost, the mass of sand needed is:

1 lb compost × (¹/₁₆ lb sand)/(⅞ lb compost).

We must evaluate the fraction (¹/₁₆)/(⅞).

Invert the denominator and multiply

(¹/₁₆)/(⅞) = ¹/₁₆ × ⁸/₇             Cancel the 8s

                      = ½ × ⅐      Multiply numerators and denominators

                      = ¹/₁₄

For 1 lb of compost, the mass of sand needed is ¹/₁₄ lb.