On a marked price, the difference of selling prices with a discount of 35% and two successive discounts of 20% and 15%, is Rs. 504. The marked price of the article (in Rs.) is:

If sec^{2} α + 4 cos^{2}α = 4 and 0° ≤ α ≤ 90°, then find the value of α.

If the simple interest on a certain sum of money borrowed for 4 years at 9.5% per annum exceeds the simple interest on the same sum for 3 years at 12.5% per annum by Rs. 225, then the sum borrowed is:

A is thrice as efficient as B. A takes 24 days less than B to complete a work. If they work together, in how many days, will the work be completed?

A tank is filled by three pipes with uniform flow. The first two pipes operating simultaneously fill the tank in the same time during which the tank is filled by the third pipe alone. The second pipe fills the tank 5 hours faster than the first pipe and 4 hours slower than the third pipe. The time required by the first pipe is: