Question
The speed of a boat in still water is 30 km/hr. If the
boat covers 240 km in upstream in 12 hours, then find the time taken by the boat to travel 140 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) = 240/12 = 20 km/hr Or, 30 – y = 20 Or, y = 30 – 20 = 10 km/hr Therefore, downstream speed of the boat = 30 + 10 = 40 km/hr Required time taken = 140/40 = 3.5 hours
ABC is a triangle. AB = 5 cm, AC = √41 cm and BC = 8 cm. AD is perpendicular to BC. What is the area (in cm2) of triangle ABD?
If O is circumcentre of acute angled triangle ABC, if ∠ BAC = 40 ˚ then ∠BOC = ?
In the given figure, B and C are the centres of the two circles. ADE is the common tangent to the two circles. If the ratio of the radius of both the ci...
O and C are the respectively orthocentre and circumcentre of ∆PQR. The line PO is extended which intersect line QR at S. such that, ∠QCR = 140°, �...
If in a ΔABC, D is a point on BC such that BD = 1cm , BC = 3 cm then what is ratio of area of ΔABD to area of ΔADC ?
The length of the each side of an equilateral triangle is 10.5 cm. The area of incircle, (cm 2 ) is
Angles of a triangle are in the ratio 3 : 4 : 8. Find the measure of the largest angle of the triangle.
Orthocenter of an right angle triangle lies on
In the given figure. ABCDEF is a regular hexagon whose side is 6 cm. APF, QAB, DCR and DES are equilateral triangles. What is the area (in cm2
- Length of a chord in a circle of radius 'r' cm, is 16 cm and distance between chord and centre of the circle is 15 cm. Find the value of (5r - 19).
Relevant for Exams:
