Quantitative Aptitude - Arithmetic Ability Questions

A boy crosses a 300 metres wide road in 30 seconds. What is his speed (in km/hr)?

The area of a square is equal to its side, if the side is 1 unit.

Find the sum of interior angles of a dodecagon?

Which of the following value of 'x' satisfies the equation 814x+4 = 2432x+8?

Two successive discounts of 12% and 20% are given by Rajat on a shirt. If the marked price of the shirt is Rs 500, then what is the value (in Rs) of discount?

If the standard deviation of a population is 6.5, what would be the population variance?

If Tan A = 15/8 and Tan B = 7/24, then Cos(A - B) = ?

A box consist of 5 rupees, 2 rupees and 1 rupee coins and their value are in the ratio of 15 : 4 : 2 respectively. If there are total 112 coins, then how many 2 rupees coins are there in the box?