This is really awesome info:-
Letters 'a', 'B, 'c' & 'd' do not appear anywhere in the spellings of 1 to 99
Letter 'd' comes for the first time in Hundred
Letters 'a', 'B & 'c' do not appear anywhere in the spellings of 1 to 999
Letter 'a' comes for the first time in Thousand)
Letters 'B & 'c' do not appear anywhere in the spellings of 1 to 999,999,999
Letter 'B comes for the first time in Billion) &
Letter 'c' does not appear anywhere in the spellings of entire English Counting....
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