Question
A boat takes 8 hours to travel 42 km upstream and 81 km
downstream combined. In another instance, it covers 48 km upstream and 54 km downstream in 7 hours. Determine the time the boat would need to travel 90 km in still water.Solution
Let the upstream and downstream speeds of the boat are x km/h and y km/h. So according to question: 42/x + 81/y = 8 And, 48/x + 54/y = 7 Let 1/x = a and 1/y = b So 42a + 81b = 8 ………. (i) And 48a + 54b = 7 …….. (ii) Solving (i) and (ii) we get a = 1/12 and b = 1/18 So x = 12 and y = 18 So the upstream and downstream speeds of the boat are 12 km/h and 18 km/h respectively. So the speed of the boat in still water = (12 + 18)/2 = 15 km/h So the time taken by the boat to cover 90 km in still water = 90/15 = 6 hoursÂ
In Which Year Did the Battle of the Hydaspes Take Place, Featuring Alexander the Great and King Porus?
What is the newly approved name of Zepto’s parent company as per the RoC filing?
The Tamil Nadu Government decided to collaborate with the Ministry of Education for what initiative?
Where was the 40th National Youth Basketball Championships held?
In what year was the Bombay Plan, advocating for economic planning in India, put forward?
_____________ won the men’s ICC Player of the Month award for December.
Which two countries will co-host the Women’s World Cup 2025 as per the ICC-UNICEF initiative?
What is the extended timeline for the Payments Infrastructure Development Fund ( PIDF ) scheme announced by the Reserve Bank of India ( RBI ) ?
For which class of students is the National Talent Search Examination (NTSE) conducted by the National Council of Educational Research and Training (NCE...
Consider the following statements about Indo-Pacific Economic Framework for Prosperity (IPEF):
1. It was launched to build economic integration...