Question

Mary has 62 square blue tiles and a number of square red tiles. All tiles are the same size. She makes a rectangle with red tiles inside and blue tiles on the perimeter. What is the largest number of red tiles she could have used?

Answer 1

perimeter of the rectangle is 2( l + b)
 = 62
dividing 2
we get 31
 the largest rectangle could be formed is of 30 and 32 tiles in length and breadth so largest no. of red tile is 32 * 30 = 960