A gallon of unleaded gasoline weighs about 6 pounds. About how many ounces does 1 quart of unleaded gasoline weigh.

Question

HINT:1 quart=1/4 of a gallon

Answer 1

To change units without changing the value, we use the Multiplicative Identity (that is, 1).

 

In this problem, we need:

    (1 gallon)=(6 pounds)      or     1 = (

    (1 quart)=(1/4 gallon)      or     (4 quarts)=(1 gallon)    or    1 = (

    (16 ounces)=(1 pound)     or    1 =

We have:

        1 quart

       (1 quart)*1

     (1 quart)*((1 gallon)/(4 quarts))

     (1 quart)*((1 gallon)/(4 quarts))*((6 pounds)/(1 gallon))*((16 ounces)/(1 pound))

    (1)*(1/4)*(6/1)*(16/1)   ounces       [note: gallons, quarts, pounds all cancel out]

        24 ounces

 

Checking:  If a gallon weighs 6 pounds, a quart weighs 1.5 pounds  [that is, 6/4]. 

      That's 24 [that is, 1.5*16] ounces.  Yes.