Arrange 2/3; 4/5; 1/2; 3/4 in descending order :

By selling 90 chocolates for Rs. 160, a chocolate trader loses 20%. How many chocolates should he sell for Rs. 96 to make a profit of 20%?

If the difference of the compound interest and the simple interest on a sum of money for 3 years is Rs. 186. Find the sum of money, if the rate of interest in both cases be 10 % 

Find value of $$ {^3\sqrt{\sqrt{0.000729}}}+^3{\sqrt{0.008}}$$

Comprehension: Read the following chart and answer the following questions.

What is the difference between the day that had maximum deaths to the day that had minimum deaths? 

A train travels the distance between station P and Q at a speed of 126 km/h, while in the opposite direction it comes back at 90 km/h. Another train travels the same distance at the average speed of the first train. The time taken by the second train to travel 525 km is:

Find the value of. 67²–33².

A can do a piece of work in 4 hours; B and C can do it in 3 hours; A and C can do it in 2 hours. How long will B along take to do it?