Multiple choice

If 20 gallons of water is added to a tub already filled with 120 gallons of water and milk, the concentration of milk in the tub will be 80 percent. What is the initial concentration of milk in the tub?

  1. 88.66 percent

  2. 90 percent

  3. 93.33 percent

  4. 96 percent

  5. 98 percent
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Initial volume = 120. Let milk = M. After adding 20, total = 140. Milk is 80% of 140 = 112. Initial concentration = 112 / 120 = 0.9333 or 93.33%.

AI explanation

Adding 20 gallons of water to the initial 120 gallons brings the total volume to 140 gallons. At an 80 percent concentration, the milk equals 0.8 times 140, or 112 gallons. Divide 112 by the original 120 gallons to find the initial concentration, which gives 0.9333, or 93.33 percent. The initial concentration of milk in the tub is 93.33 percent.

Keep practicing — related questions