The average weight of boys in a class is 30 kg and the average weight of girls in the same class is 20kg. If the average weight of the whole class is 23.25 kg, what could be the possible strength of boys and girls respectively in the same class?

Correct Answer: 83.33 ml

Explanation:

Profit (%) = 9.09 % = 1/11

 

Since the ratio of water and milk is  1 : 11,

 

Therefore the ratio of water is to mixture = 1:12

 

Thus the quantity of water in mixture of 1 liter = 1000 x (1/12) = 83.33 ml

Correct Answer: 30

Explanation:

pool : kerosene 

   3  :  2(initially) 

   2  :  3(after replacement)

 

  R e m a i n i n g Q u a n t i t y I n i t i a l Q u a n t i t y = 1 - R e p l a c e d Q u a n t i t y T o t a l Q u a n t i t y

 

(for petrol)    2 3 = 1 - 10 k

 => K = 30

 Therefore the total quantity of the mixture in the container is 30 liters.

Correct Answer: 5

Explanation:

           Wine                         Water

            8L                              32L

            1                :               4

           20 %                           80% (original ratio)

           30 %                           70% (required ratio)

 

In  ths case, the percentage of water being reduced when the mixture is being replaced with wine.

 

so the ratio of left quantity to the initial quantity is 7:8

 

Therefore ,  7 8 = 1 - K 40

 

=> K = 5 Lit

Correct Answer: Rs. 18

Explanation:

Let the price of the mixed variety be Rs. x per kg. By the rule of alligation, we have :

 

Cost of 1 kg of type 1 rice           Cost of 1 kg of type 2 rice  

 

 

 

 

?(20-x)/(x-15) = 2/3 

? 60 - 3x = 2x - 30

  ? x = 18.

Correct Answer: 63 Kg

Explanation:

By the rule of alligation:

C.P. of 1 kg sugar of 1st kind      C.P. of 1 kg sugar of 2nd kind 

 

  

 

Therefore, Ratio of quantities of 1st and 2nd kind = 14 : 6 = 7 : 3. 

Let x kg of sugar of 1st kind be mixed with 27 kg of 2nd kind. 

Then, 7 : 3 = x : 27 or x = (7 x 27 / 3) = 63 kg.

Correct Answer: 32

Correct Answer: 2:3

Explanation:

By the rule of alligation:
Cost of 1 kg rice of 1st kind                  Cost of 1 kg rice of 2nd kind 

 

 

  Required ratio = 60 : 90 = 2 : 3

Correct Answer: 5:3

Explanation:

W 1 : A 1 W 2 : A 2 . . . . . W N : A N

  2 : 3                   4 : 5                    5 : 7 

 

W 1 W 1 + A 1 = 2 5 W 2 W 2 + A 2 = 4 9 W N W N + A N = 5 12

= 72/180

= 80/180

= 75/180  

                     

 

 =>     5   :   3

 

Therefore, the ratio is  5: 3

Correct Answer: 5 litres

Explanation:

Total quantity of mixture = 75 litre

Milk  :  Water  =  4  :  1   

            

                   3       :       1

Correct Answer: 15

Explanation:

Let quantity of mixture be x liters.

 

Suppose a container contains x units of liquid from which y units are taken out and replaced by Water. After operations , the quantity of pure liquid =  x 1 - y x n units, Where n = no of operations . 

 

So, Quantity of Milk =  x 1 - 6 x 2  

 

Given that, Milk : Water = 9 : 16 

 

=> Milk : (Milk + Water) = 9 : (9+16)

 

=> Milk : Mixture = 9 : 25 

 

 Therefore,  x 1 - 6 x 2 x = 9 25

 

=> x = 15 liters