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 7.5 hours to travel 750 km downstream, then find the time taken by boat ‘B’ to travel 210 km upstream and 330 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 = 750/7.5 Or, 10x = 100 Or, x = 10 Therefore, upstream speed of boat ‘B’ = 9x – 2x = 7x = 70 km/hr Downstream speed of boat ‘B’ = 9x + 2x = 11x = 110 km/hr Required time taken = (210/70) + (330/110) = 3 + 3 = 6 hours
Consider the following statements about unemployment:
1. Frictional unemployment occurs due to short-term transitions in the labor market.
Match the following women with their achievements:
- The Sao Joao festival is a traditional annual celebration in which Indian state?
Which of the following countries is not a part of the European Free Trade Association block?
World Refugee Day is celebrated on which of the following days?
Tanjore Balasaraswati was a dancer of which of the following dance forms?
Which Gurudwara is located near Pratap Gate in Kaithal town of Haryana?
Who authored the book Hind Swaraj, which discusses self-rule and critiques modern civilization?
- Which individual was confirmed by the US Senate as the Director of the National Institutes of Health (NIH)?
- In which month of the Hindu calendar is the famous Jagannath Rath Yatra held?
Relevant for Exams:
