Chapter 6.2, Problem 22PPS

To determine

To find the item that has the better unit price if one gallon of milk sells for $3.18 and 1 quart of milk sells $0.76.

Answer to Problem 22PPS

1 quart of milk selling for $0.76 is better unit price.

Explanation of Solution

Given information :  One gallon of milk sells for $3.18 and 1 quart of milk sells $0.76.

Formulaused : Per unit price will be calculated using following formula :

Per unit price $=\frac{\text{ Total amount of milk }}{\text{ Total cost of that milk }}$

And also to use following conversion formula :

1 gallon = 4 quarts

Calculation :First method : Here as one gallon of milk sells for $3.18 that means 4 quarts of milk sells for $3.18, so cost of 1 quart of such type of milk

  $=\frac{3.18}{4}=\$0.795$

And the cost of 1 quart of another type of milk is $0.76

So, clearly0.76 <0.795

Second method :Given one gallon of first type of milk costs $3.18

Now as 1 quart cost of second type of milk is $0.76

So using above conversion formula, 1 gallon cost of such type of milk 0.76 x 4=$3.04

Or, 3.04 <3.18

Conclusion :Based on both methods,it is cleared that 1 quarts for $0.76 sell is the better unit price.