good solution.. thanks :)
What is the number of non-congruent Rectangles in a chess board?
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2 Answers
Lokesh Verma
·2008-09-26 22:12:57
This is a novel problem. Seeing it for the first time..
The answer is same as the number of sets {a,b} such that
0<9
This will be same as number of (a,b) such that 0< a <=b<9
8C2+8
Explanation:
8C2 is the number of ways to select a,b such that a not equal to b and has the other conditions 0<8
8 is the number of ways to select a,b such that a=b
Thus, the total is 8.7/2 + 8 = 28+8 = 36