Ten different of an are given. Words with five letters are formed from these given letters. Then what will be the number of words which have at least one letter repeated?

Mathematices

Sana and Ripa earn in the ratio 2: 1. They spend in the ratio 5: 3 and save in the ratio 4: 1. If the total monthly savings of both Sana and Ripa are Tk. 5,000, calculate the monthly income of Ripa.

Mathematices

A certain amount increases by 60% in six years at a simple interest rate. What will be the interest of Tk. 12,000 after 3 years at the same rate compounded annually?

Mathematices

In a square field of side 30 meters, 4 cows are grazing the field as they are tied at each of the four corners with a 14 meter long rope for each cow. What is the ungrazed area in the field?

Mathematices

There are two examination rooms A and B. If 10 students are sent from A to B, then the number of students in each room is the same. If 20 candidates are sent from B to A then the number of students in A is double the number of students in B. What is the number of students in room A?

Mathematices

If m and n are whole numbers such that $m^n$ prime prime =121, then the value of (m - 1)^{(n + 1)}  is: