The diagonal of a square is equal to the side of an equilateral triangle. If the area of the square is 15√3 sq cm, what is the area of the equilateral triangle?
Two trains are moving in opposite directions with the same speed. If the length of each train is 120 metres and they cross each other in 12 seconds, then what is the speed (in km/hr) of each train?
The average revenues of 7 consecutive years of a company is Rs 83 lakhs. If the average of first 4 years is Rs 78 lakhs and that of last 4 years is Rs 90 lakhs, find the revenue for the 4th year.
Present age of R and S are in the ratio of 3 : 2 respectively. If the present age of H is 117 years and R’s present age is 4/13 of H’s present age, then after how many years the ages of R and S would be in the ratio of 15 : 11?