1. 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, what is the weight of B?
1. 31 kg
2. 2812 kg
3. 32 kg
4. 3012 kg
Answer & Explanation Answer:- 1 Explanation :- Total weight of A, B & C = 45 x 3 = 135 2. If the average marks of three batches of 55, 60 and 45 students respectively is 50, 55, 60, what is the average marks of all the students? Answer & Explanation Answer:- 2 Explanation :- Average marks of All students = [(55*50) + (60*55) + (45*60)] / (55 + 60 + 45) 3. 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. What is the present age of the husband? Answer & Explanation Answer:- 1 Explanation :- Sum of the present ages of husband, wife and child = (27 * 3 + 3 * 3) years = 90 years. 4. The average weight of 8 person’s increases by 2.5 kg when a new person comes in place of one of them weighing Answer & Explanation Answer:- 3 Explanation :- Total weight increased = 2.5 * 8 = 20. 5. 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 & Explanation Answer:- 2 Explanation :- Average weight of Whole Class = [(36*40) + (44*35)] / (36 + 44) = (1440 + 1540)/ 80 = 37.25 kg
Total Weight of A & B = 40 x 2 = 80 ———(1)
Total Weight of B & C = 43 x 2 = 86 ———(2)
Adding (1) & (2)
A + B + B + C = 80 + 86 = 166
But we know , Total weight of A, B & C (A+ B + C) = 45 x 3 = 135
Therefore 135 + B = 166
B = 166 – 135 = 31 kg
B’s weight = 31 kg.
1. 53.23
2. 54.68
3. 51.33
4. 50
= (2750 + 3300 + 2700) / (160)
= (8750/160) = 54.68
1. 40
2. 32
3. 28
4. 30
Sum of the present ages of wife and child = (20 * 2 + 5 * 2) years = 50 years.
Husband’s present age = (90 – 50) years = 40 years
65 kg. What is the weight of the new person?
1. 75 Kg
2. 50 Kg
3. 85 Kg
4. 80 Kg
weight of new person = 65 + 20 = 85
1. 38.25
2. 37.25
3. 38.5
4. 37