Quantitative Aptitude - Arithmetic Ability Questions

A card is drawn from a pack of 52 cards. What is the probability that either card is black or a king? 

A, B and C can do a job working alone in 12, 16 and 24 days respectively. In how many days they can do the job if they worked together?

What is the rate of interest (in %) if simple interest earned on a certain sum for the 3 years is Rs 6,000 and compound interest earned for 2 years is Rs 4,160?

If a number is decreased by 10%, it becomes 54. To make it 72, it should be increased by

If xy = 22 and x2+ y2= 100, then what will be the value of (x + y)?

U and V started a business by investing amounts Rs 184000 and Rs 224000 respectively. If U’s share in the profit received at the end of year is Rs 20700, then what will be the total profit (in Rs)earned by them together?

To travel 612 km, an Express train takes 9 hours more than Rajdhani. If the speed of the Express train is doubled, it takes 3 hours less than Rajdhani. The speed (in km/hr) of Rajdhani is

5% discount is offered on an item. By applying a promo code the customer wins 20% cash back. What is the effective discount?