[31 kg] The average weight of A, B and C is 45 kg. If the average weight of A and B be 40 kg and that of B a

For Competitive Exams

The average weight of A, B and C is 45 kg. If the average weight of A and B be 40 kg and that of B and C be 43 kg, then the weight of B is:

17 kg

20 kg

26 kg

31 kg

Explanation:

Let A, B, C represent their respective weights. Then, we have:

A + B + C = $\left(45 \times 3\right)$ = 135 .... (i)

A + B = $\left(40 \times 2\right)$ = 80 .... (ii)

B + C = $\left(43 \times 2\right)$ = 86 ....(iii)

Adding (ii) and (iii), we get: A + 2B + C = 166 .... (iv)

Subtracting (i) from (iv), we get : B = 31.

$\therefore$ Bs weight = 31 kg.

Additional Questions

A grocer has a sale of Rs. 6435, Rs. 6927, Rs. 6855, Rs. 7230 and Rs. 6562 for 5 consecutive months. How much sale must he have in the sixth month so that he gets an average sale of Rs. 6500?	Answer
Distance between two stations A and B is 778 km. A train covers the journey from A to B at 84 km per hour and returns back to A with a uniform speed of 56km per hour. Find the average speed of the train during the whole journey?	Answer
The average monthly income of P and Q is Rs. 5050. The average monthly income of Q and R is Rs. 6250 and the average monthly income of P and R is Rs. 5200. The monthly income of P is:	Answer
There are two divisions A and B of a class, consisting of 36 and 44 students respectively. If the average weight of divisions A is 40 kg and that of division b is 35 kg. What is the average weight of the whole class?	Answer
A batsman makes a score of 87 runs in the 17th inning and thus increases his averages by 3. What is his average after 17th inning?	Answer
In the first 10 overs of a cricket game, the run rate was only 3.2. What should be the run rate in the remaining 40 overs to reach the target of 282 runs?	Answer
The average age of 36 students in a group is 14 years. When teachers age is included to it, the average increases by one. Find out the teachers age in years?	Answer
The average age of husband, wife and their child 3 years ago was 27 years and that of wife and the child 5 years ago was 20 years. The present age of the husband is:	Answer
A car owner buys petrol at Rs.7.50, Rs. 8 and Rs. 8.50 per litre for three successive years. What approximately is the average cost per litre of petrol if he spends Rs. 4000 each year?	Answer
The average weight of A, B and C is 45 kg. If the average weight of A and B be 40 kg and that of B and C be 43 kg, then the weight of B is:	Answer

Share with Friends