25 buses are running between two places P and Q. In how many ways can a person go from P to Q and return by a different bus?
Correct Answer : B
There are 8436 steel balls, each with a radius of 1 centimeter, stacked in a pile, with 1 ball on top, 3 balls in the second layer, 6 in the third layer, 10 in the fourth, and so on. The number of horizontal layers in the pile is
In the figure below, the rectangle at the corner measures 10 cm 20 cm. The corner A of the rectangle is also a point on the circumference of the circle. What is the radius of the circle in cm?
In the figure given below, AB is the chord of a circle with center O. AB is extended to C such that BC = OB. The straight line CO is produced to meet the circle at D. If ACD = y degrees and AOD = x degrees such that x = ky, then the value of k is