Mixture and alligation handwritten notes

 Mixture and alligation 

Mixture and alligation handwritten notes 

Complete math notes

Formulas 

Q 1 Cost of two types of pulses is Rs.15 and Rs, 20 per kg, respectively. If both the pulses are mixed together in the ratio 2:3, then what should be the price of mixed variety of pulses per kg? 

1. Rs. 22 per kg
2. Rs. 30 per kg
3. Rs. 10 per kg
4. Rs. 18 per kg
5. Rs. 24 per kg

Answer: (4) Rs. 18 per kg

Solution:

Let the cost of mixed variety of pulse be Rs. x

As per the alligation rule,

2:3 = (20-x) : (x-15)

⇒ 2x+3x = 60+30

⇒ 5x = 90

⇒ x = 18

Q 2  A dealer has 1000 kg sugar and he sells a part of it at 8% profit and the rest of it at 18% profit. The overall profit he earns is 14%. What is the quantity which is sold at 18% profit?

1. 250 kg
2. 600 kg
3. 620 kg
4. 400 kg
5. 450 kg

Answer: (2) 600 kg

Solution:

As per the rule of alligation,

Quantity of Dearer: Quantity of Cheaper = (18-14) : (14-8) = 4:6 = 2:3

Quantity of sugar sold at 18% profit = 3/5 × 1000 = 600kg

Q 3 . How much coffee of variety A, costing Rs. 5 a kg should be added to 20 kg of Type B coffee at Rs. 12 a kg so that the cost of the two coffee variety mixture be worth Rs. 7 a kg?

1. 25 kg
2. 34 kg
3. 55 kg
4. 52 kg
5. 50 kg

Answer: (5) 50 kg

Solution:

As per the rule of alligation, 

Quantity of Dearer: Quantity of Cheaper = (12-7) : (7-5) = 5:2

Quantity of Variety A coffee that needs to be mixed ⇒ 5:2 = x:20

⇒ x =50 kg