Question
Find the number of words that can be formed by using all
letters of the word 'LAPTOP', if order of vowels remains same.Solution
Total words “LAPTOP”= 6 Number of vowels (A, O) = 2 But in these, we cannot change the order of vowels. Suppose the required ways be 'n' multiplied by 2! ways with 'n' must be given 6! => 2! × n = 6! => n = 360 ways
A 540-metre long train takes 9 seconds to cross a pole. If it takes 33 seconds to cross a bridge, then find the length of the bridge. (in km)
A 360 m long train crosses a platform twice its length in 2 min. Find the speed of the train.
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A train, which is moving at the rate of 60 miles per hour, is brought to rest in 3 minutes with a uniform retardation, find this retardation, and also t...
A train 450 metre long takes 45 sec to cross a man running at a speed of 4 km/hr in the direction same to that of train. What is the speed of the train?
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