John is supposed to walk from his house to park every morning. One morning he is in real hurry and wants to save atleast 1/3rd of the time. By how much percentage he should increase his speed.
a).100% b)33% c) 66% d) 50%
Let the distance between his house and park be 100 metres.
Let’s assume he takes 30 minutes daily. Hence his speed would be 100/30.
One day, if he wishes to save 1/3rd of 30 minutes, that is 10 minutes, he should cover the distance in 20 minutes in which case his speed would be 100/20.
Required increment in speed = (Required increment in speed / Original Speed) * 100 % = ((100/20 – 100/30)/100/30)* 100% = 50%
Can you give a simple formula to find average of sum of squares of first n natural numbers?
(n + 1) (2n + 1) /6 can be used to calculate the average of sum of first n natural numbers.
Given Log x (ab) and logx (a/b), how you will find logx a
: Log x (ab) can be written as logx (a) + logx (b) ……..equation 1.
logx (a/b) can be written as logx (a) – logx (b) ……..equation 2.
Solving equation 1 and 2 we will get logx (a) = Log x (ab) + logx (a/b)/ 2)
Consider a rhombus with diagonals of lengths d1 and d2. What could be its area?
Area of the rhombus = ½(d1 * d2)
Can you quickly tell the ratio of the volume of a cylinder of height h to that of another cylinder of unit height but with same radius?
Height h is the answer.
Reason: Volume V1 of Cylinder of height h and radius r, V1 = IIr2 h
Volume V2 of another Cylinder of unit height of same radius r,
V2 = IIr2h /9by substituting 1 for h) Now answer is V1/V2 = h.