An article seller allows a discount of 10% on the marked price. He gets 30% commission from the publisher. What will be his profit percentage?

Study the following graph carefully to answer the given questions

 T and V started the work. After 3 days Z joined them, who can complete alone the same whole work in 3 days. What is the total number of days in which they had completed the work?

If $$ {0.7\over 1-6c}=-0.2$$ then what is the value of c.

In a two - digit number, the digit at the unit's place is 1 less than twice the digit at the ten's place. If the digits at units and ten's place are interchanged, the difference between the new and the original number is less than the original number by 20. The original number is: 

If $$ {x^{12}+x^{3}\over {x^{6}}}=0$$ find $$ {x^{36}+{1\over x^{36}}}$$

Difference of two numbers is 1890. If 12.5% of one number is 17.5% of the other number, Find the two numbers.

A can do a work in 6 days and B can do the same work in 12 days. If A, B and C together can do the same work in 4 days, then in how much days C can do it alone?

The average temperature of Monday, Tuesday, Wednesday and Thursday is 60°. The average temperature for Tuesday, Wednesday, Thursday and Friday is 63°. If the ratio of temperature for Monday and Friday is 21 : 25, then what is the temperature of Friday ?