Question
The speed of a boat in still water is 40 km/hr. If the
boat covers 360 km in upstream in 12 hours, then find the time taken by the boat to travel 150 km in downstream.Solution
Let the speed of the boat in still water and the speed of the current be ‘x’ km/hr and ‘y’ km/hr, respectively Upstream speed of the boat = (x – y) = 360/12 = 30 km/hr Or, 40 – y = 30 Or, y = 40 – 30 = 10 km/hr Therefore, downstream speed of the boat = 40 + 10 = 50 km/hr Required time taken = 150/50 = 3 hours
If 27x3 - 8y3 = (3x - Ay) X (Bx2 + 4y2 + Cxy), then find the value of 3 X (2A + 6B) - 2C.
Solve the inequality:
(x − 1)/(x + 2) > 2.
Which of the following represents the solution set?
(A) x < −5
(B) −5 < x <...
In Δ ABC, ∠ B= 68° and ∠ C 32°. Sides AB and AC are produced to points D and E, respectively. The bisectors of ∠ DBC and ∠...
If x – 1/x = 9, then x3 – 1/x3 is:
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What will come in place of the question mark (?) in the following series?
23, 46, ?, 184, 368, 736
If x = 19, then the value of x5 - 20x4 + 20x3 - 20x2 + 20x - 1 is
If √k + (1/√k) = 8, then find the value of k + (1/k).
