A sum was invested at simple interest at a certain rate for 11 years. Had it been invested at a rate which is 8% higher than the previous one, it would have fetched Rs. 1936 more. What is the sum ?

There are seven letters in the word COUNTRY and two vowels O and U. Considering two vowels as one unit, total number of letters will be 5 + 1 = 6. So, number of arrangements = 61 Now, the two vowels can be arranged in 21 ways among themselves.

From a basket containing 5 black and 8 white balls, two draws of one ball each are made without replacement. What is the probability that one is black and the other is white ?

A person sold 3/5 of a consignment at a profit of 35% and the rest at a loss of 25%. If there was an overall profit of `715 what is the actual cost of the consignment ?