self Maths Puzzle

nine sqaures are choosen at random on a chess board.what is the probability that they form a square of sizes 3*3?
1) 9/64c9
2)36/64c9
3)1/64c9
4)none

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self Other Question

What distance must be covered, if a vehicle with front wheel having radius of 7 feet revolves 7 more revolutions as compared to the back wheel with the radius of 14 feet ? a number consists of three digits.in that three digits middle one is equal to sum of the other two and sum of those 3 digits is 10.if we reverse the number it increased by 99.what is the number?