Solve the puzzle

3+4=9
1+2=7
45+67=18
9+7=9
1+6=8
2+3=?​

Given this information, which expression must represent the value of b?

Adam drew two same size rectangles and divided them into the same number of equal parts. he shaded 1/3 of one rectangle and 1/4 of the other rectangle. what is the least number of parts into which both rectangles could be divided into?

Which of the following is the result of expanding the series