Multiple choice general knowledge math & puzzles

How many gallons of water must be mixed with 1 gallon of a 15-percent salt solution to obtain a 10-percent salt solution?

  1. 0.50

  2. 1.00

  3. 0.67

  4. 1.50
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Let x be gallons of water added. The salt amount stays constant: 0.15 gallons (15% of 1 gallon). Final concentration: 0.15/(1+x) = 0.10. Solving: 0.15 = 0.10 + 0.10x, so 0.05 = 0.10x, giving x = 0.5. The dilution formula is: C1V1 = C2V2 where C2 is the target concentration and V2 is the final total volume.

Keep practicing — related questions