Question
Ratio of still water speeds of three boats is 3:4:5. The
first boat travels downstream, the second and third boats travel upstream. They travel in streams of speed ratio 2:2:3 so that the ratio of effective speed of the boats is 5:2:2. If the effective speed of the first boat is 15 km/hr more than the effective speed of the third boat, what is the sum of their still water speeds?Solution
Ratio of their still water speeds = 3:4:5 Let their still water speeds be 3x, 4x and 5x Stream speed is in the ratio 2:2:3 Let the stream speeds be 2y, 2y and 3y ∴ Their effective speeds are (3x + 2y), (4x - 2y), (5x - 3y) respectively. (3x + 2y): (4x - 2y): (5x - 3y) = 5:2:2 => (3x + 2y)/5 = (4x - 2y)/2 => 20x - 10y = 6x + 4y => 14x = 14y => x = y ∴ Their effective speeds are 5x, 2x and 2x respectively. Given, 5x = 2x + 15 => 3x = 15 => x = 5 Sum of their still water speeds = 3x + 4x + 5x = 12x = 12 ×  5 = 60 km/hr.
What is the main objective of the Agricultural Produce Marketing (Development and Regulation) Rules, 2007?
Jute is extracted from the bark of the white jute plant (Corchorus capsularis). Family of Jute is _________________.
How many and what type of bonds are present in NH4+?
In the poultry industry, a female chicken is called Hen after________weeks when it is ready to lay eggs?
The light soil which need frequent irrigation and have low water retention capacity are
Pest population at a damaging level?
FAO stand for__________________
chickens have one of the most efficient digestive systems in the animal kingdom, which one is known as true stomach?Â
Which of the following is/are used as molecular diagnostics of plant diseases?
What will be the error d.f. for a R.B.D. field experiment with 8 treatments and 3 replications?
Relevant for Exams:
