Arithmatical -Time and Distance
DIRECTIONS : Problems based on time and distance.
1. |
An express train travelled at an average speed of 100 km/hr, stopping for 3 minutes after every 75 km. How long did it take to reach its destination 600 km from the starting point? |
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A. 6 hrs 21 min |
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B. 6 hrs 24 min |
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C. 6 hrs 27 min |
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D. 6 hrs 30 min |
Solution |
Time taken to cover 600 km | = (600/100)hrs |
=6 hrs. |
Number of stoppages | = 600/75 - 1 |
=7. |
Total Time of stoppages | = (3 x 7)min |
=21 min. |
Hence,total time taken=6 hrs 21 min. |
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2. |
Sound is said to travel in air at about 1100 feet per second. A man hears the axe striking the tree, 11/5 seconds after he sees it strike the tree. How far is the man from the wood chopper? |
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A. 2197 ft |
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B. 2420 ft |
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C. 2500 ft |
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D. 2629 ft |
Solution |
Distance | = (1100 x 11/5)feet |
= 2420 feet. |
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3. |
The speed of a car increases by 2 kms after every one hour. If the distance travelling in the first one hour was 35 kms. what was the total distance travelled in 12 hours? |
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A. 456 kms |
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B. 482 kms |
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C. 552 kms |
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D. 556 kms |
Solution |
Total distance travelled in 12 hours | =(35+37+39+.....upto 12 terms) |
This is an A.P with first term, a=35, number of terms, n= 12,d=2. |
Required distance | = 12/2[2 x 35+{12-1) x 2] |
=6(70+23) |
= 552 kms. |
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4. |
A person croses a 600 m long street in 5 minutes. What is his speed in km per hour? |
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A. 3.6 |
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B. 7.2 |
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C. 8.4 |
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D. 10 |
Solution |
Speed | =(600 / 5 x 60)m/sec |
= 2 m/sec |
=(2 x 18/5)km/hr |
= 7.2 km/hr. |
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5. |
A train travels at an average of 50 miles per hour for 2x1/2 hours and then travels at a speed of 70 miles per hour for 1x1/2 hours. How far did the train travels in the entire 4 hours? |
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A. 120 miles |
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B. 150 miles |
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C. 200 miles |
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D. 230 miles |
Solution |
Total distance travelled | = [(50 x 2x1/2)+(70x1x1/2)] |
= (125+105)miles |
= 230miles. |
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