What is the number of fives used in numbering a 260-page book?

If the sum of the two-digit numbers AB and CD is the three-digit number 1CE, where the letters A, B, C, D, E denote distinct digits, then what is the value of A?

P’s salary is 20% lower than Q’s salary which is 20% lower than R’s salary. By how much percent is R’s salary more than P’s salary?

Let X be a two-digit number and Y be another two-digit number formed by interchanging the digits of X. If $(X + Y)$ is the greatest two-digit number, then what is the number of possible values of X?

A Question is given followed by two Statements I and II. Consider the Question and the Statements. A certain amount was distributed among X, Y and Z. Question: Who received the least amount?

Statement-I: X received $\frac{4}{5}$ of what Y and Z together received. Statement-II: Y received $\frac{2}{7}$ of what X and Z together received.

Which one of the following is correct in respect of the above Question and the Statements?

Three numbers $x$, $y$, $z$ are selected from the set of the first seven natural numbers such that $x > 2y > 3z$. How many such distinct triplets $(x, y, z)$ are possible?