In how many ways can 5 people from a group of 6 people be seated around a circle table?

The average of a, b, c is 6 and a - b = 4, ab = 21; What is the value of c?

A train of 220 m long is moving at 45 km/h. The time taken by the trian to cross a tunnel of 260 m long is-/ একটি ২২০ মিটার দীর্ঘ ট্রেন ৪৫ কিমি/ঘণ্টা বেগে চলেছে। ২৬০ মিটার দীর্ঘ একটি টানেল অতিক্রম করতে ট্রেনটি যে সময় নেবে তা হল-

What is the angle between any two sides of an equilateral triangle?

a, b, c, d and e are five consecutive integers in increasing order of size. Which one of the following expression is not odd?

If a + b = 4 and ab = -12, then a - b equals to-