How many 2 digit numbers from 1- 100?

Answer 1

90

10-20=10

20-30=10

30-40=10

40-50=10

50-60=10

60-70=10

70-80=10

80-90=10

90-99=9

Thus, the answer is actually 89 two-digit numbers between 1 and 100. You do not count 100 itself because it is NOT a two-digit number, it is a three-digit number. On top of that, you begin your counting at 10, since 10 is the FIRST two-digit number in the sequence. Then the answer should be sligtly more clear.

Answer 2

90

Answer 3

91