Question 209310
The  1st  odd  2  digit  number >30  is,,,,,,31
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The  last  odd 2  digit number (less  than 100)  is,,,,99
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99-31=68 total  number gaps,,,,,divided  by  2(odd & even) = 34 number  gaps
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since  we  are  counting  1st  and  last,  add  1  to  gap = 35  total  numbers
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checking, 31,33,35,37, 39,,,,,makes 5  numbers  for  the  30's
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This  repeats  for  the  40's, 50's, 60's, 70's, 80's,and 90's,,,or 7  times
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5*7=35  total  numbers,,,,ok
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