Raphael,

Imagine you are going to put flooring tiles on this rectangle. These tiles are square and larger than normal, they are 1 yard by 1 yard so each tile has an area of 1 square yard. You start along the long side and put down 23 tiles. Then you repeat that row and put down 23 more tiles. You repeat this 7 time to lay down 7 rows of 23 tiles each for a total of 23 × 7 = 161 tiles. Each tile cover an area of 1 square yard so you have covered 161 square yards.

Penny