Direction: what should come in place at question mark(?).

$$ {\sqrt{4489}+(71)^{2}-(?)^{2}=2707}$$

A can built a wall in 8 days while B can destroy the same wall in 3 days. A start the work and worked for 6 days, during the last 2 days of which B also joins him. In how many days A can finish the remaining work alone?

ΔPQR is right angled at Q. If cos P = 3/5, then what is the value of cos R?

Directions: The bar graph given below shows the production (in ' 000 tones) of rice of a country for the year 2007 to 2011. Study the graph carefully and answer the question given below it.

The production of rice in the year 2011 is what percent of the production of rice in 2010?

The speed of a boat in still water is 10 km/hr. It covers (upstream) a distance of 45 km in 6 hours. The speed (in km/hr) of the stream is : 

In an isosceles triangles ABC, AB=AC the median drawn on the same arms are perpendicular to each other find AB/BC?

A circle with radius 42 cm is drawn. What will be length of arc of a sector subtending an angle of 60 degrees at the Centre?

The ratio of circumradius and hypotenuse a right-angled triangle is