5. Lets start from the easy ones. The total number of squares on a chessboard (of any size) is ______.
From Quiz Mathemagic!
Answer:
204
This one may seem easy to you, but it is not that easy!
Many may know that number of squares in a chessboard is 64. But, the question is "total number of squares in a chessboard".
We only count the single squares, But not the combined ones. Let me explain(please draw a chessboard in a paper for your convenience to understand it).
First, as usual, count the single squares on the chessboard. There are 8 horizontally and 8 vertically, i.e,
8 x 8 = 64 in total.
Then, count the squares, made by combining 4 single squares. There are 7 horizontally and 7 vertically, i.e,
7 x 7 = 49 in total.
Then, count the squares, made by combining 9 single squares. There are 6 horizontally and 6 vertically, i.e,
6 x 6 = 36 in total.
Then, count the ones, made by combining 16 single squares. There are
5 x 5 = 25 in total
Continue in this pattern.
It may appear:
8 square + 7 square + 6 square + 5 square + 4 square + 3 square + 2 square + 1,
which makes a total of 204 squares, which is the answer.