If tan⁻¹(k) + tan⁻¹(1/2) = π/4, then what is the value of k ?

What is the arithmetic mean of 8², 9², 10², …, 15²?

Let X be a random variable following binomial distribution whose mean and variance are 200…

The probability of a man hitting a target is 1/5. If the man fires 7…

If two fair dice are tossed, then what is the probability that the sum of…

If P(A) = 1/3, P(B) = 1/2 and P(A ∩ B) = 1/4, then what…