Mixtures and Alligation Questions

Multiple choice
  1. 25%

  2. 40%

  3. 30%

  4. 20%

Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Total cost = (25 × 32) + (15 × 36) = 800 + 540 = Rs.1340 for 40 kg rice. Cost price per kg = 1340/40 = Rs.33.50 per kg. Selling price = Rs.40.20 per kg. Profit per kg = 40.20 - 33.50 = Rs.6.70. Profit percent = (6.70/33.50) × 100 = 20%. Option D is correct. At 20% profit on Rs.33.50, the selling price is 33.50 × 1.20 = Rs.40.20, which matches.

Multiple choice
  1. First

  2. Second

  3. Third

  4. Fourth

Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Compare milk:water ratios as fractions: Container 1 (5:3 = 1.67), Container 2 (2:1 = 2.00), Container 3 (3:2 = 1.50), Container 4 (7:4 = 1.75). The minimum milk-to-water ratio is 1.5 in Container 3. Option B (Second) has ratio 2:1 = 2, which is higher. The question asks for minimum milk relative to water, meaning smallest ratio.

Multiple choice
  1. $8 : 5$
  2. $5 : 8$
  3. $6 : 5$
  4. $5 : 6$
  5. $Cannot be determined$
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Let milk = M. Adding 25L water gives ratio 12:5, so M:25 = 12:5, meaning M = 60L. Initial mixture: 60L milk + 25L water = 85L total. Ratio is 60:25 = 12:5 ✓. Drawing 17L mixture: milk removed = 17×(12/17) = 12L, water removed = 17×(5/17) = 5L. Remaining: milk = 60-12 = 48L, water = 25-5 = 20L. Adding 10L water: milk = 48L, water = 20+10 = 30L. New ratio = 48:30 = 8:5 ✓

Multiple choice
  1. 25 : 29

  2. 9 : 10

  3. 27 : 29

  4. 27 : 31

Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

In first mixture (20L, ratio 3:7): milk = 3/10 × 20 = 6L, water = 7/10 × 20 = 14L. In second mixture (36L, ratio 7:5): milk = 7/12 × 36 = 21L, water = 5/12 × 36 = 15L. When mixed: total milk = 6 + 21 = 27L, total water = 14 + 15 = 29L. Ratio = 27:29. Option A (25:29) undercounts milk, option B (9:10) simplifies incorrectly, and option D (27:31) overcounts water.

Multiple choice
  1. 2

  2. 3.33

  3. 4

  4. 5

  5. Can't be determined

Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Cost price of mixture = 60 / 1.20 = Rs. 50/kg (since sold at 20% profit). Using allegation: Let second variety be x kg. First variety (Rs. 40) and third variety (Rs. 60, 2 kg) mix to give Rs. 50. Ratio 40 : 60 = 10 : 10 = 1 : 1. So 2 kg of third variety needs 2 kg of first variety. Average of (40 and 60) is 50. Now allegation between average 50 (from 2+2=4kg) and second variety 48 to get 50: 50 is at 4:1 ratio from 48 and 50, so second variety = 4 × 1 = 4 kg. Wait, let me reconsider. (40×2 + 60×2)/(2+2) = 200/4 = 50. So 4 kg at Rs. 50. To maintain Rs. 50 when mixing with Rs. 48, we need ratio 48:50 = 2:2, meaning equal quantities. So 4 kg of Rs. 48 type.

Multiple choice
  1. 2 : 1

  2. 2 : 3

  3. 3 : 2

  4. 1 : 2

Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Original alloy 17.5 kg has copper:zinc = 5:2. Copper = (5/7)×17.5 = 12.5 kg, Zinc = (2/7)×17.5 = 5 kg. Adding 1.250 kg zinc: new zinc = 5 + 1.250 = 6.250 kg. New ratio copper:zinc = 12.5:6.25 = 2:1.

Multiple choice
  1. 20%

  2. 25%

  3. 33.33%

  4. 16.67%

Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Original mixture: 20% of 15L = 3L alcohol, 12L water. After adding 3L water, total = 18L, alcohol still = 3L. New percentage = (3/18)×100 = 16.67%. This is a dilution problem - alcohol amount stays constant while total volume increases.

Multiple choice
  1. $5: 2$
  2. $3: 5$
  3. $2: 5$
  4. $5: 3$
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

In 25 litres, acid is 4×5 = 20 litres and water is 5 litres (since 4:1 ratio means 4 parts acid and 1 part water, total 5 parts). After adding 3 litres water, total water becomes 8 litres while acid remains 20 litres. The new ratio is 20:8 = 5:2 after dividing by 4. Therefore, option A is correct.

Multiple choice
  1. 12 litre/लीटर

  2. 10 litre/लीटर

  3. 14 litre/लीटर

  4. 16 litre/लीटर

Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Let milk = 4x, water = 3x. Adding 5 litres water gives 4x : (3x + 5) = 4 : 5. So 5(4x) = 4(3x + 5), giving 20x = 12x + 20, so 8x = 20, x = 2.5. Milk quantity = 4x = 10 litres.

Multiple choice
  1. 6L

  2. 4L

  3. 5L

  4. 10L

Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Selling at cost price with 25% profit means SP = 1.25 × CP_milk. Let water added be x liters. Total quantity = 20+x, selling at CP of 20L milk. So 20×CP = (20+x)×0.8×CP. Solving: 20 = 16 + 0.8x, so 0.8x = 4, x = 5L. Options A, B, D don't satisfy this condition.

Multiple choice
  1. 3 : 7

  2. 10 : 7

  3. 7 : 10

  4. 7 : 3

Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Vessel A has ratio 4:1 (milk:water), so in any quantity from A, milk is 4/5 and water is 1/5. Vessel B has ratio 3:2, so milk is 3/5 and water is 2/5. Taking x liters from each: Milk from A = 4x/5, Milk from B = 3x/5, Total milk = 7x/5. Water from A = x/5, Water from B = 2x/5, Total water = 3x/5. The ratio in C is (7x/5):(3x/5) = 7:3. Options A, B, and C have incorrect milk-to-water ratios.

Multiple choice
  1. 411 : 540

  2. 401 : 544

  3. 417 : 564

  4. 407 : 560

Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Three containers have equal volume. Taking total volume as 3×(2+3) = 15, 3×(3+4) = 21, 3×(4+5) = 27. For LCM of denominators, scale: 2:3 becomes 2/5:3/5, 3:4 becomes 3/7:4/7, 4:5 becomes 4/9:5/9. Taking common denominator 315: milk = (2×63 + 3×45 + 4×35) = 126+135+140 = 401, water = (3×63 + 4×45 + 5×35) = 189+180+175 = 544. Ratio = 401:544.

Multiple choice
  1. $20 : 7$
  2. $8 : 3$
  3. $27 : 4$
  4. $25 : 9$
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Glass 1 has milk:water = 3:5, so milk fraction = 3/8. Glass 2 has milk:water = 6:1, so milk fraction = 6/7. For final 1:1 ratio, milk fraction = 1/2. Using alligation: mix 3/8 and 6/7 to get 1/2. The ratio is (6/7 - 1/2):(1/2 - 3/8) = (5/14):(1/8) = 20:7. Option A is correct.

Multiple choice
  1. 5 : 8

  2. 8 : 5

  3. 3 : 2

  4. 2 : 3

  5. 10 : 3

Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Initially, milk:water = 12:5 after adding 25L water, so milk = 60L (12×5), water = 25L. Total = 85L. When 17L mixture is removed, milk removed = 17×(12/17) = 12L, water removed = 17×(5/17) = 5L. Remaining: milk = 48L, water = 20L. Adding 10L water gives final ratio 48:30 = 8:5.