Math and Puzzles - Mixed Problem Set
A comprehensive collection of math and puzzle questions covering work and time, speed and distance, number patterns, profit and loss, interest calculations, geometry, and logical reasoning.
Questions
If the radius of a circle is diminished by 10%, then its area is diminished by:
- 0.1
- 0.19
- 0.2
- 0.36
A boat travels 20 kms upstream in 6 hrs and 18 kms downstream in 4 hrs.Find the speed of the boat in still water and the speed of the water current?
- 1/2 kmph
- 7/12 kmph
- 5 kmph
- none of these
At what time after 4.00 p.m. is the minutes hand of a clock exactly aligned with the hour hand?
- 0.181822916666667
- 0.185989583333333
- 0.14015625
- 0.181765046296296
A person has 4 coins each of different denomination. What is the number of different sums of money the person can form (using one or more coins at a time)?
- 16
- 15
- 12
- 11
The simple interest on a certain sum of money for 3 years is 225 and the compound interest on the same sum at the same rate for 2 years is 153 then the principal invested is
- 1500
- 2250
- 3000
- 1875
A cow is tethered in the middle of a field with a 14 feet long rope. If the cow grazes 100 sq. ft. per day, then approximately what time will be taken by the cow to graze the whole field ?
- 2 days
- 6 days
- 18 days
- 24 days
2 hours after a freight train leaves Delhi a passenger train leaves the same station travelling in the same direction at an average speed of 16 km/hr. After travelling 4 hrs the passenger train overtakes the freight train. The average speed of the freight train was?
- 40
- 30
- 80
- 60
8 15 24 35 48 63 ?
- 70
- 80
- 75
- 88
2 numbers differ by 5.If their product is 336,then the sum of the 2 numbers is:
- 21
- 51
- 28
- 37
Which number is the odd one out? 9678 4572 5261 3527 7768
- 7768
- 3527
- 4572
- 9678
A radio when sold at a certain price gives a gain of 20%. What will be the gain percent, if sold for thrice the price?
- 280
- 270
- 290
- 260
Thirty men take 20 days to complete a job working 9 hours a day. How many hour a day should 40 men work to complete the job?
- 8 hrs
- 7 1/2 hrs
- 7 hrs
- 9 hrs
A and B can do a piece of work in 45 days and 40 days respectively. They began to do the work together but A leaves after some days and then B completed the remaining work n 23 days. The number of days after which A left the work was
- 9
- 11
- 12
- 15
A shop keeper sold a T.V set for Rs.17,940 with a discount of 8% and earned a profit of 19.6%.What would have been the percentage of profit earned if no discount was offered?
- 24.8%
- 25%
- 26.4%
- None of these
A clock is set right at 8 a.m. The clock gains 10 minutes in 24 hours. What will be the true time when the clock indicates 1 p.m. on the following day?
- 48 min. past 12
- 38 min. past 12
- 28 min. past 12
- 25 min. past 12
What is the missing number in this series? 8 2 14 6 11 ? 14 6 18 12
- 16
- 9
- 15
- 6
Dinesh travelled 1200 km by air which formed 2/5 of his trip. One third of the whole trip, he travelled by car and the rest of the journey he performed by train. What was the distance travelled by train?
- 600Km
- 700Km
- 800Km
- 900Km
A train which travels at a uniform speed due to some mechanical fault after traveling for an hour goes at 3/5th of the original speed and reaches the destination 2 hrs late.If the fault had occurred after traveling another 50 miles the train would have reached 40 min earlier. What is distance between the two stations.
- 300
- 310
- 320
- 305
The average between a two digit number and the number obtained by interchanging the digits is 9. What is the difference between the two digits of the number?
- 8
- 2
- 5
- Cannot be determined
Pipe A can fill in 20 minutes and Pipe B in 30 mins and Pipe C can empty the same in 40 mins.If all of them work together, find the time taken to fill the tank
- 17 1/7 mins
- 20 mins
- 8 mins
- none of these