The height of a light house is 20 meters above sea level. The angle of depression (from the top of the lighthouse) of a ship in the sea is 30°. What is the distance of the ship from the foot of the light house?

Three bottles of equal capacity are containing a mixture of milk and water in ratio 1: 3, 3: 5 and 11: 5 respectively. These three bottles are emptied into a large bottle. What is the ratio of milk and water respectively in this large bottle?

How many seconds will a 500-meter-long train take to cross a man walking with a speed of 3 km/hr. in the direction of the moving train if the speed of the train is 63 km/hr? 

A solid metallic sphere of radius x cm is melted and then drawn into 126 cones each of radius 3.5 cm and height 3 cm. There is no wastage of material in this process. What is the value of x?

If the ratio of two numbers is 13 : 15 and their L.C.M. is 39780. Then the numbers are?

In a school with 600 students the average age of the boys is 12 years and that of the girl is 11 years. If he average age of the students is 11 years 9 months, then the number of girls in the school is

Cost of 18 shirts and 45 trousers is Rs 68,400. What is the cost of 10 shirts and 25 trousers?

A sum of money was lent at simple interest at certain rate for 3 years. Had it been lent at 2.5 % per annum higher rate, it would have fetched ₹ 540 more. The money lent was