A boat running upstream takes 7 hours and 40 minutes to cover a certain distance while it takes 5 hours to cover the same distance downstream. What is the ratio between the speed of the current and speed of the boat respectively? 

In a race of 200 metres, B can give a start of 10 metres to A and C can give a start of 20 metres to B. The start that C can give to A, in the same race, is

Find the area of the circle formed in an equilateral triangle of side 42 cm. Using (π=22/7)

A polygon has 9 sides, what is its interior angle?

What will be the compound interest (nearest to Rs. 1 on a sum of Rs. 25,000 for 2 years at 12% p.a., if the interest is compounded 8-monthly?

A man rows from J to K (upstream) and back from K to J (downstream) in a total time of 15 hours. The distance between J and K is 300 km. The time taken by the man to row 9 km downstream is identical to the time taken by him to row 3 km upstream. What is the approximate speed of the boat in still water?

An arc of 30 ° in one circle is double an arc in a second circle, the radius of which is three times the radius of the first. Then the angles subtended by the arc of the second circle at its center is 

The distance between the points (4, 8) and (k, -4) is 13. What is the value of k?