Question 816680
i don't believe there is just one answer.
you need to solve this logically.
assume the tens digit is equal to 1.
the units digit has to be greater than 2.
that means the number could be:
13
14
15
16
17
18
19
in all of the cases above where the tens digit is equal to 1, the units digit is more than 2 times the tens digit.
now assume the units digit is 2.
that means the number could be:
25
26
27
28
29
in all of the cases above where the tens digit is equal to 2, the units digit is more than 2 times the tens digit.
now assume the units digit is 3.
that means the number could be:
37
38
39
in all of the cases above where the tens digit is equal to 3, the units digit is more than 2 times the tens digit.
now assume the units digit is 4.
that means the number could be:
49
in all of the cases above where the tens digit is equal to 4, the units digit is more than 2 times the tens digit.
now assume the units digit is 5.
there are no units digit that are more than 2 times 5 so there are no more cases where you can have the units digit be more than 2 times the tens digit.
the only cases are when the tens digit is from 1 to 4.
once the tens digit is 5 or more, you have no more cases.