Quantitative Aptitude - Arithmetic Ability Questions

9 hrs after a goods train passed a station, another train travelling at a speed of 72 km/hr following that goods train passed through that station. If after passing the station the train overtakes the goods train in 3 hours. What is the speed of the goods train?

In a college, the ratio of boys to girls is 29 : 33 respectively. When 142 more boys join the college, this ratio becomes 21 :19. How many more girls should join the college to make the number of boys and girls equal?

What is the measure of an interior angle of a regular Octagon?

The average revenues of 7 consecutive years of a company is Rs 75 lakhs. If the average of first 4 years is Rs 70 lakhs and that of last 4 years is Rs 82 lakhs, what will be the revenue for the 4th year.

The mean of a distribution is 15 and the standard deviation is 5. What is the value of the coefficient variation?

The compound interest earned in two years at 12% per annum is Rs 10176. What is the sum (in Rs) invested?

The value of x for which the expressions 7x + 13 and 13x - 7 become equal is _____

If 9x2 + 16y2 = 60 and 3x + 4y = 6, then the value of xy is