Question

A dairy needs 357 gallons of milk containing 5% butterfat. How many gallons each of milk containing 7% butterfat and milk containing 1% butterfat must be used to obtain the desired 357 gallons?

Answer 1

9514 1404 393

Answer:

• 238 gallons 7%
• 119 gallons 1%

Explanation:

Let h represent the number of gallons of high butterfat content milk. Then 357-h will be the number of gallons of 1% milk. The total amount of butterfat in the mix is ...

0.07h +0.01(357 -h) = 0.05(357)

0.06h = 14.28 . . . . . . . . . . subtract 3.57, collect terms

h = 238 . . . . . . . . . . divide by 0.06

357-h = 357 -238 = 119

238 gallons of 7% and 119 gallons of 1% are needed.