Question

all the two digit natural numbers are selected which have their unit digit greater then the tens digit

Answer 1

10 21 30 31 32 40 41 42 43 50 51 52 53 54 60 61 62 63 64 65 70 71 72 73 74 75 76 80 81 82 83 84 85 86 87 90 91 92 93 94 95 96 97 98

=44

Answer 2

All two digit natural numbers having their unit digit greater than the tens digit

Definition:

Natural numbers is a number that occurs commonly and obviously in nature .Natural number starts with $N=[0,1,2..]$

Step-by-step explanation:

In this section we deal with two digit natural numbers ,hence they start with $N=[10,11,12..99]$.

Another condition is given ,that is the numbers should have their unit digit greater than the tens digit ,this happens at the following numbers

$12,13,14,15,16,17,18,19,23,24,25,26,27,28,29,34,35,36,37,38,39,45,46,47,48,49,56$$,57,58,59,67,68,69,78,79,89$

Therefore,,the total number of two digit natural numbers which have their unit digit greater then the tens digit is 36.