MATEMATIKA BILINGUAL Part 2

SPESIAL FOR RSBI and SSN Class for Schoolarship

Let's Try and View The Solution here 

Question : 4    A jogger running at 9 kmph alongside a railway track in 240 metres ahead of the engine
of a 120 metres long train running at 45 kmph in the same direction. In how much time
will the train pass the jogger?

1. 3.6 sec
2. 18 sec
3. 36 sec
4. 72 sec

Correct Answer :    C
Explanation :
Speed of train relative to jogger = (45 - 9) km/hr = 36 km/hr.
= 36 x (5/18) m/sec
= 10 m/sec.
Distance to be covered = (240 + 120) m = 360 m.
Time taken = 360/10 = 36 sec

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Question : 5    A goods train runs at the speed of 72 kmph and crosses a 250 m long platform in 26 seconds. What is the length of the goods train?

1. 230 m
2. 240 m
3. 260 m
4. 270 m

Correct Answer :    D
Explanation :
Speed = 72 x (5/18) = 20 m/sec. Time = 26 sec. Let the length of the train be x metres. Then, (x + 250)/26 = 20
x + 250 = 520
x = 270