A person travels from x to y at a speed of 40Km/h and returns by increasing his speed 50%. What is his average speed for both the trips?

A. 36km/h
B. 45km/h
C. 48km/h
D. 50km/h

Answer

Correct Answer: C. 48km/h

Solution

Speed of person from x to y =40 km/h
Speed of person from y to x =(40×150)/100 = 60km/h
Since the distance traveled is the same
Therefore, Average Speed = (2x40x60)/40+60 = 48km/h

The average age of a 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:

A. 35 years
B. 30 years
C. 40 years
D. None of these

Answer

Correct Answer: C. 40 years

Solution

27×3+3×3=90 hsbnd,wife n child
20×2+5×2=50 wide n child
Hsbnd age= 90-50
= 40 yrs

A cricketer has a certain average for 10 innings. In the eleventh inning, he scored 108 runs, there by increasing his average by 6 runs. His new average is:

A. 48 runs
B. 52 runs
C. 55 runs
D. 60 runs

Answer

Correct Answer: A. 48 runs

Solution

Let average for 10 innings be x. Then,

(10x + 108)/11 = x + 6
= 11x + 66 = 10x + 108
= x = 42.
New average = (x + 6) = 48 runs 

The average monthly income of P and Q is Rs. 5050. The average monthly income of Q and R is 6250 and the average monthly income of P and R is Rs. 5200. The monthly income of P is:

A. Rs. 3500
B. Rs. 4000
C. Rs. 4050
D. Rs. 5000

Answer

Correct Answer: B. Rs. 4000

Solution

Let P, Q and R represent their respective monthly incomes. Then, we have:

P + Q = (5050 * 2) = 10100 — (i)
Q + R = (6250 * 2) = 12500 — (ii)
P + R = (5200 * 2) = 10400 — (iii)
Adding (i), (ii) and (iii), we get:
2(P + Q + R) = 33000 = P + Q + R = 16500 — (iv)
Subtracting (ii) from (iv), we get, P = 4000.
P’s monthly income = Rs. 4000

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:

A. 17 kg
B. 20 kg
C. 26 kg
D. 31 kg

Answer

Correct Answer: D. 31 kg

Solution

Let A, B, C represent their respective weights.

Then, we have:
A + B + C = (45 * 3) = 135 — (i)
A + B = (40 * 2) = 80 — (ii)
B + C = (43 * 2) = 86 — (iii)
Adding (ii) and (iii), we get: A + 2B + C = 166 — (iv)
Subtracting (i) from (iv), we get: B = 31
B’s weight = 31 kg