Quantitative Aptitude - Arithmetic Ability Questions

If a - b = 10 and ab =-21, then what is the value of a3-b3 ?

Of the 5 numbers whose average is 72, the first is 1/8 times the sum of other 4. The first number is _____.

A, B and C invest in a business in the ratio 4 : 5 : 7. C is a sleeping partner, so his share of profits will be half of what it would have been if he were a working partner. If they make Rs 36,000 profit of which 25% is reinvested in the business, how much does B get (in Rs)?

In the given figure, radius of a circle is 14√2 cm. PQRS is a square. EFGH, ABCD, WXYZ and LMNO are 4 identical squares. What is the total area (in sq.cm) of all the small squares ?

The angles of elevation of the top of a tree 220 meters high from two points lie on the same plane are 30° and 45°. What is the distance (in metres) between the two points?

If Rs. 10000 amounts to Rs. 11664 invested in compound interest(compounded annually) for two years then the annual rate of compound interest is

Pranita got 30 marks more in Math than what she got in Science. Her Math marks are 60% of the sum of her Math and Science marks. What are her Science marks?

20% discount is offered on an item. By applying a promo code the customer wins 10% cash back. What is the effective discount?