1.
You along with your 9 friends can finish a 1 kg delicious chocolate cake in 10 minutes, then you alone can finish the cake in how many minutes?(Assume all are of equal efficiencies)
Correct Answer
A. 100
Explanation
If you can finish together in 10 mins, it takes a longer time for you to do alone right????????? so 10*10 = 100
2.
You and your friend travel from office to park. You start at 8.00 am and your friend start one hour late. Your travel at the rate of 10 km/hr and your friend travels twice the speed as yourself. At what time you both meet? Also find the distance travelled by your friend from the start.
Correct Answer
A. 10.00 am, 20 km
Explanation
Since you start at 8.00 am and your friend starts one hour later, your friend starts at 9.00 am. You travel at a rate of 10 km/hr, so in 2 hours (from 8.00 am to 10.00 am), you would have traveled 20 km. Your friend travels at twice your speed, so they would have traveled 20 km as well. Therefore, you both meet at 10.00 am and your friend has traveled 20 km from the start.
3.
If A is the brother of B. B is the sister of C. Also D is the son of C. How is D related to B?
Correct Answer
C. Nephew
Explanation
Gender of D is unknown, hence we cannot determine the relation. If D is male, then Nephew. If D is female, then Niece.
4.
Which dates fall under November 1993 (Thursday) ?
Correct Answer
A. 4, 11, 18, 25
Explanation
The dates 4, 11, 18, and 25 fall under November 1993 (Thursday) because these dates occur on Thursdays in November 1993.
5.
Point A is at 5 km distance to the north east of point B. Point C is at east of B. The distance between B and C is 3000 meters. Find the perimeter of the figure formed after joining.
Correct Answer
A. 12 km
Explanation
A is north east of B and C is east of B . This figure forms a right angled triangle. By pythagoras theorem, we find AC to be 4 km. Hence perimeter is 5+3+4 = 12 km.
6.
You walk at the rate of 5 km/hr inside a moving train along the train direction. The train is running at the speed of 100 km/hr. Also a man walks at the rate of 10 km/hr in the opposite direction outside the train. Find the relative speed between the man and the train. Also find the relative speed between you and the man.
Correct Answer
A. 110, 115
.
Explanation
For the 1st part of question, add speed of man and speed of train(travelling in opposite directions). so 100+10= 110. For the second part of the question, the relative speed is [ (5+100) + 10 ] = 115. Your speed get added up with trains speed because you are walkinh inside the train along the train's direction. Also the frame of reference is with respect to some man outside the train.
7.
You can fill a tank in 2 hours. Your friend can leak the same tank in 4 hours. Both start working together and after 1 hour your friend leaves. Find the time taken by you to fill the remaining part of the tank?
Correct Answer
A. 1 hour 30 mins
Explanation
By solving with lcm method, lcm of 2, 4 is 4. So your efifciency is 2 l/h and your friend's efficiency is 1 l/h. Total efficiency per hour is 2 - 1 = 1. (-1 because its leak). Now together work for 1 hour. so (2-1)*1 = 1 litre of tank is filled. Now remaining part of tank is 3 litres. You alone work. hence time taken will be 3 / 2 = 1.5 hours = 1 hour 30 mins.
8.
You go to a mall. Your walk at the rate of of 1 m/s. You want to have fun. Hence you travel upwards in the escalator which moves down at the rate of 10m/s. Find the time taken by you to reach up the escalator of length 54 m.
Correct Answer
A. 1/10 mins
Explanation
Escalator concept is similar to concept of boats and streams. When you walk upwards and when the escalator is moving downwards, the net speed will reduce and it will be 10-1 = 9 m/s. Hence time taken will be length of escalator / net speed = 54 / 9 = 6 seconds = 6/60 mins = 1/ 10 mins.
9.
The average of 1st three consecutive numbers is x. Find the average of 1st four numbers.
Correct Answer
A. X+0.5
Explanation
Since the numbers are consecutive and also the average of 1st three numbers is x, thus the 2nd number is x. So 1st number is x-1, 3rd number is x+1, 4th number is x+2. Now the average of 1st four numbers is (x-1 + x+2 )/2 = x+0.5
10.
If the area of rectangle is increased by 10 % and its height is decreased by 10 %, then find the net effective change in its volume?
Correct Answer
A. 1 % decrease
Explanation
Volume= area * height. Hence, substituting x=a+b+(ab)/100, net effective change in volue is -1 %(i.e 1 % decrease).
OR
New volume = [ 1.1(area) * 0.9(height) ] = 0.99 * original volume. Hence % change in volume = (1-0.99)/1 * 100 = 1 %