The value of $$ cos {20^o} cos {40^o}cos {60^o}cos {80^o}$$ is:

A shopkeeper list the price of an article as ₹ 500. But he gives a certain discount which allows the buyer to pay ₹ 500 for the article including 10% sales tax. The rate of discount is 

If $$ {tan3A=cot{(2A+40)}}$$ then find the value of $$ {tan^2{3A}}+{cot^{4}3A}$$.

A work is done by 30 workers not all of them have the same capacity to work. Every day exactly 2 workers, do the work with no pair of workers working together twice. Even after all possible pairs have worked once, all the workers together works for six more days to finish the work. Find the number of days in which all the workers together will finish the work?

A discount of 20% in the price of rice enables X to buy 5 kg more rice for ₹100. What is the reduced price of rice per kg?

A shopkeeper cheats to the extent of 10% while buying and selling fruits, by using tampered weights. His total gain , in percentage is:

Directions: Bar graph given below shows pens sold by a retailor on five different days. Study the data carefully and answer the following questions.

Sum of volume of cylinder (S) and volume off cone (C) is 2190𝝅 cm² & height of both cylinder and cone is same i.e, 10 cm. If radius of cone is 15 cm then find the ratio of radius of S to radius of C?

Pipes A and B can fill a tank in 12 minutes and 15 minutes, respectively. The tank when full can be emptied by pipe C in x minutes. When all the three pipes are opened simultaneously, the tank is full in 10 minutes. The value of x is: