ATQ,
Let the length of the train = ‘x’ metres Then, distance covered by the train in 13 seconds = ‘x’ metres Distance covered by the train in 18 seconds = (x + 150) metres So, distance covered by the train in 5 seconds i.e. (18 – 13) seconds = (x + 150 – x) metres So, speed of the train = (150/5) = 30 m/s Length of the train = 30 × 13 = 390 metres Relative speed of the train with respect to the dog who is walking in opposite direction = 30 – 4 = 26 m/s So, time taken by the train to cross the dog = 390 ÷ 26 = 15 seconds.
How many straight lines can be formed from 9 points out of which 4 are colinear?
5 persons P, Q, R, S, and T are sitting around a round table. How many times can they sit in different ways so that Q and T do not sit together?
In how ways can the selection be made so that a particular member is always excluded?
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In how many different ways can the letter of the word ‘PRAISE’ be arranged?
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An examinee is required to answer the eight questions out of 16 questions which are divided into two groups each containing eight questions each and he...
From 6 officers and 8 Jawans, in how many ways can 5 be chosen to include exactly 3 officers?
