Hello everyone, it’s another beautiful day to put the brain into work by providing the solutions for the daily math challenge. I’m delighted to share my solution for 06/03/2025 math problem for the day. Without much time being wasted I would like to present and explain in details how I got my solution.
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So, from the question we are asked to find the number of positive 3 digit numbers that exist. So the first thing I did was to assume those 3 positive digits; X, Y and Z. And for the products of the digits X, Y and Z to be odd, then all digits between 1 to 9 must be odd also. This is because if any even number is introduced the product of X, Y and Z might be even.
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Having established that fact, the next thing I did was to figure out the possible values for X, which falls between the range 1 to 9. That is to say that X belongs to that set of odd numbers {1, 3, 5, 7, 9}. I went further to get the total number of elements in set X ie n(X) which gives me a single value 5. Same approach I used to obtain the set of Y and also the number of elements in set Y and same for Z.
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After obtaining all the number of elements for each digits, I proceeded to find the products of the number of elements for X, Y and Z, which finally gives us the product of the 3 positive digits to be 125 (which is an odd number).
See below the complete process:
Image is mine
Tools Used:
Graphics Tab/Pen
Laptop and
Mirror Online Whiteboard
