Question
A man rows 40 km upstream and 60 km downstream in 8
hours. If the ratio of his upstream speed to downstream speed is 2:3, then find the time required to travel 30 km upstream and 45 km downstream.Solution
ATQ,
Let the upstream and downstream speeds be 2x km/hr and 3x km/hr respectively. So, 40/2x + 60/3x = 8 = 20/x + 20/x = 8 = 40/x = 8 ⇒ x = 5 Required time = 30/2x + 45/3x = 30/10 + 45/15 = 3 + 3 = 6 hours
Find the area of triangle having sides 20 m, 21 m, and 29 m.
If G is the centroid and AD, BE, CF are three medians of ∆ABC with area 54 cm 2 , then the area of ∆BGD is?
The 2nd approximation to a root of the equation x2-x-1-0 in the interval (1, 2) by Bisection method will be:
In the given figure, ABC is a right angled triangle. ∠ ABC = 90 0and ∠ ACB = 60 0. If the radius of the smaller circle is 2 cm...
MN is a diameter of a circle with centre O. The tangent at 'P' meets MN produced at 'Q'. If ∠PMN = 44 ° , then find ∠PNQ.
What will be inradius of an equilateral triangle of side 2 cm?
AB and AC are two Chords of a circle with centre O. M and N are the mid points of the chords respectively. The line OM and ON are extended which interse...
In the given figure, two identical circles of radius 4 cm touch each other. A and B are the centres of the two circles. If RQ is a tangent to the circle...
At the centre of a circle of 20 cm radius, the angle made by an arc of 24(4/9) cm length is
Determine the difference between an angle and its complementary angle, given that the angle is two-thirds of its complement.
Relevant for Exams:
