Iam a 2-digit number. the sum of my digits is 11. the tens digit is odd. the ones digit is 3 less than the tens digit. what number am i

Our two digit number has two digits, and let's say that T is in the tens place and U is in the units (or ones place). The number looks like this: TU

As a result, T and U are our variables.

We are told the sum of the digits is 11, so T + U = 11.

We are told the ones digit is 3 less than the tens digit. Translating that, we have U = T - 3.

We take the two equations we made and solve their system.

T + U = 11 (1)

U = T - 3  (2)

Number the equations as (1) and (2) for ease, and we solve them by substitution since (2) is solved for U; U on one side of the equals and not U on the other.

T + U = 11          < equation (1)

T + T - 3 = 11     <put (2) into (1)

2T - 3 = 11         <collect like terms

2T = 14            <add 3 to both sides

T = 7                < divide both sides by 2

Since the sum of the digits is 11 - - our equation (1), we put T  = 7 into (1)

T + U = 11

7 + U = 11

4 = U

This makes our number 74. Now let's check. The digits add to 11, 7 is odd, and the ones is less. Bingo.

Therefore the mystery number is 74.

your answer would be 12