Question
The ratio of the speed of boats ‘A’ and ‘B’ in
still water is 8:9, respectively. The speed of the current is 25% of the speed of boat ‘A’ in still water. If boat ‘A’ takes 8.5 hours to travel 680 km downstream, then find the time taken by boat ‘B’ to travel 84 km upstream and 220 km downstream. (Note: Both the boats are rowing in the same stream.)Solution
Let the speeds of boats ‘A’ and ‘B’ in still water be 8x km/hr and 9x km/hr Therefore, speed of the current = 0.25 × 8x = 2x km/hr According to the question, 8x + 2x = 680/8.5 Or, 10x = 80 Or, x = 8 Therefore, upstream speed of boat ‘B’ = 9x – 2x = 7x = 56 km/hr Downstream speed of boat ‘B’ = 9x + 2x = 11x = 88 km/hr Required time taken = (84/56) + (220/88) = 1.5 + 2.5 = 4 hours
Which one of the following statements is true with regard to the image formation by two eyes of a person?
Three different positions of the same dice are shown. Find the number, which can be on the face opposite the face showing '6'.
‘Operation Spider’s Web’ recently seen in the News, has been conducted by which of the following countries?
Which of the following were members of the States Reorganisation Commission (SRC), 1953?
1. K.M. Panikkar
2. H.N. Kunzru
3. P...
In the context of accounting, the term IFRS stands for
Consider the following statements regarding the informal workforce in India:
I. Around 91% of India’s workforce is engaged in the informal sect...
According to “The child labour prohibition and regulations act 1986” how many hours of overtime can be taken from a young child?
Which of the statements given below are correct regarding the Start-ups in India?
1. They are less than a decade old entity with a turnover less ...
Which one of the following will not be reduced by metallic zine?
What is the minimum number of employees required for an establishment to be covered under the Employees’ Provident Funds and Miscellaneous Provision A...