A vessel contains 20 liters of a mixture of milk and water in the ratio 3:2. 10 liters of the mixture are removed and replaced with an equal quantity of pure milk. If the process is repeated once more, find the ratio of milk and water in the final mixture obtained?
Correct answer: A. 9:1
- A. 9:1
- B. 4:7
- C. 7:1
- D. 2:5
Explanation
Initially there are 12 litres of milk and 8 litres of water. Removing 10 litres removes 6 litres of milk and 4 litres of water, leaving 6 litres and 4 litres; after adding 10 litres of milk, the quantities are 16 litres and 4 litres. Repeating the process leaves 8 litres of milk and 2 litres of water, then adding 10 litres of milk gives 18 litres : 2 litres = 9:1. The likely mistake is option c, 7:1, from subtracting the wrong proportions during the second replacement.
Last updated
About Ratio and Proportion
Ratios compare quantities in the same units, while proportions state that two ratios are equal. Problems cover simplification, division in a given ratio, direct and inverse variation, scale, and missing terms, with attention to the difference between a ratio and a fraction representing part of a whole.
Practise Arithmetic
1,060 free Arithmetic MCQs from Mathematics, each with the correct answer and an explanation. Unlimited attempts, no account needed.
Exams that ask Mathematics questions like this
Mathematics is on 67 papers prepared for on TestUstad, and all of them draw the same bank, so this question is worth knowing for every one of them.