If P : Q : R = 6 : 7 : 8 and R : S = 3 : 5, then what is P : S?

X and Y give an exam. Difference of their marks is 45 and the difference of their marks is 15% of the maximum marks. What is the maximum marks for the exam?

The area of a right angled triangle ABC, right angled at B, is 46 sq units. A median is drawn from A to BC which intersects at D. Find the area (in sq. units)of triangle ABD.

In a triangle ABC, a line is drawn from C which bisects AB at point D. Find the ratio of area of the triangles DBC and ABC.

If x + y + z = 6 and xy + zx + zy = 10, then find the value of x3 + y3 + z3 - 3xyz

If p = 72-72-72-72-.....∞, then find the value of 2p2+1?

Find the number of prime factor of 20790.

Find the value of  21623 + 36-1 2