Quantitative Aptitude - Arithmetic Ability Questions

What is the altitude of an equilateral triangle whose side is 12 cm?

In a bag the ratio of red balls to green balls is 4 : 9. If 6 more green balls were added to the bag, the ratio of red balls to green balls would become 1 : 3. How many red balls are there in the bag?

If the value of √42 is approximately 6.480, then what is the approximate value of √(6/7)?

Find the value of x if 1-x24 = 1318

What is the value of sin ­-300°?

tan3A is equal to

If the shopkeeper sells an item at Rs 4400 which is marked as Rs 5000, then what is the discount that he is offering?

The marked price of a pen is Rs 3000. The shopkeeper gives two successive discounts of 15% and a% to the customer. If the customer pays Rs 2142 for the pen, then what is the value (in percentage) of a?