a b
a = b+1
3 </= a </= 8
has to be odd if prime so b is 1,3,5,7, (not 9 if a = b+1)
list from Google search:
31, 37, 41, 43, 47, 53, 59, 61, 67, 71, 73, 79
43 is the only one I see where a=b+1 or 4 = 3+1
*I am a 2-digit whole number between 30 and 80.
*My tens digit is one more than my ones digit.
*I am a prime number.
What number am I
3 answers
the number ends in 1,3,7,9
So the candidates are 21, 43, 89
Only 43 fits the description
So the candidates are 21, 43, 89
Only 43 fits the description
LOL so ends in 1, 3, 7 ! not 5 OR 9