Question
The speed of a boat in still water is 10.5 times the
speed of the stream. If the difference between the upstream and downstream speed of the boats is 26 km/hr, then find the time taken by the boat to travel 494 km in upstream.Solution
Let the speed of the stream be ‘x’ km/hr Therefore, speed of the boat in still water = 10.5x km/hr Upstream speed of the boat = 10.5x – x = 9.5x km/hr Downstream speed of the boat = x + 10.5x = 11.5x km/hr According to the question, 11.5x – 9.5x = 26 => 2x = 26 => x = 13 Therefore, upstream speed of the boat = 9.5x = 123.5 km/hr Required time taken = 494/123.5 = 4 hours
For given pair of equations, how many solutions are possible?
3x + 4y = 15 and 6x + 8y = 10
For given pair of equations, how many solutions are possible?
4x + 6y = 16 and 8x + 12y = 32
The ratio of roots of the equation mx2 + nx + n = 0 is α/ β = a/b, then find the value of `sqrt(a/b)+sqrt(b/a)+sqrt(n/m)`
Find the area between the lines 18x +12y = 108, 9x  + 6y  = 27, x - axis and y -axis.Â
If in two linear equations ax + by = c and dx + ey = f and a/d = b/e = c/f then, which of the following is true about the two equations?
For which value of m, there is no solution to the equation -
a – b = 5
ma – 4b = 1
The lines x + y = 9 and x - y = 3 intersect at point P. Find the coordinates of P.
Solve: (x/3) + (x/5) = 16
Find the value of 'a' and 'b' which satisfy the following equations:
9a + 7b = 30
4a - 5b = 62
If (5√P - 7√Q) = 5, [1.5P = 4Q-(R/3)+9] and (√P/√Q) = 1.6, then find out the value of ‘R’.