If  $$ {2\ sinθ-cos θ\over {cosθ+sinθ}}=1$$, then value of cotθ is:

If cosec 39°= x, the value of $$ {1\over {cosec^{2}{51°}}} +sin^{2} 39^{°}+tan^{2}{51^{°}}-{1\over {sin^{2}{51^{°}}}{Sec^{2}{39^{°}}}}$$ is-

16 children are to be divided into two group A and B consisting of 10 and 6 children. The average percent marks obtained by the children of Group A is 75 and the average percent marks of all the 16 children is 76. What is the average percent marks of children of Group B?

The population of a village was 9600. In a year, with the increase in population of males by 8 % and that of females by 5 %, the population of the village became 10272. What was the number of males in the village before increase?

If the radius of a right circular cylinder is decreased by 50% and its height is increased by 60%, its volume will be decreased by

A, B and C enter into a partner ship with capitals in the ratio 5 : 6 :8. At the end of business term, they received the profits in the ratio 5 : 3 :12. Find the ratio of time for which they contributed their capitals?

At present, the sum of the ages of A, B and C is 150 years, whereas 10 years ago, the ratio of their age was 5:4:3. Find the ratio of their ages 10 years hence.

Three pipes A, B and C can fill a cistern in 6 hours. After working at it together for 2 hours, C is closed and A and B can fill the remaining part in 7 hours. The time taken by C alone to fill the cistern is_