The average of a collection of 20 measurements was calculated to be 56 cm . But later it was found that a mistake had occurred in one of the measurements which was recorded as 64 cm, but should have been 61 cm. The correct average must be: 

If Diagonal of rectangle is 41 cm and one side of Rectangle is 9 cm Then find out Ratio of perimeter and area of Rectangle? 

In triangle ABC, F is the centroid. If AB=11 cm, BC=14 cm and AC=7 cm, then what is the value (in cm) of EF?

If the number x3339 is divisible by 11, what is the face value of x?

Six years ago, the ratio of the ages of the two persons P and Q was 3:2. Four years hence the ratio of their ages will be 8:7. What is P’s age?

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

What will come in place of the question mark (?) in each of the following series?

15     ?    24    33     97    122     

$${I. \sqrt{200x}+\sqrt{102}=0}$$
$${II.\sqrt{160y}+\sqrt{200}=0}$$