A boat goes 15 km in an hour in still water, and takes thrice the time to cover the same distance upstream. The speed of the current (in km / hr) is –

A watch is sold at a profit of 25%. Had it been sold for Rs.120 less then, there would have been a less then of 15%. What is the cost price in rupees?

What is the sum of all three-digit numbers which are divisible by 20?

A business Rs. 3500 Starts from, after 5 months B becomes his partner, after one year the profit between the two is divided in the ratio of 2: 3, then find the capital investment of B.

A can paint a house in 55 days and B can do it 66 days. Along with C, they did the job in 12 days only. Then, C alone can do the job in how many days?

A certain sum of money at a certain rate doubles itself in 9 years, then in how many years it will become the same sum will be 5 times of itself?

The HCF of two numbers is 96 and their LCM is 1296. If one of the numbers is 864, the other is

A's 2 days work is equal to B's 3  days work. If A can complete the work in 8 days, then to complete the work B will take: