45 : 5 + 7 * 4 = 37
Вычисления:
45 : 5 + 7 * 4 = 9 + 28 = 37
1) 45 : 5 = 9
2) 7 * 4 = 28

300 − (132 + 91) = 77
Вычисления:
300 − (132 + 91) = 300 − 223 = 77
1) (132 +91) = 233
$\begin{array}{r}\begin{array}{r}+\end{array}\underline{\begin{array}{r}132\\ 91\end{array}}\\ \begin{array}{r}223\end{array}\end{array}$
$\begin{array}{r}\begin{array}{r}-\end{array}\underline{\begin{array}{r}300\\ 223\end{array}}\\ \begin{array}{r}77\end{array}\end{array}$

24 : 4 * 5 − (17 − 9) = 22
Вычисления:
24 : 4 * 5 − (17 − 9) = 30 − 8 = 22
1) 24 : 4 * 5 = 6 * 5 = 30
2) (17 − 9) = 8
$\begin{array}{r}\begin{array}{r}-\end{array}\underline{\begin{array}{r}17\\ 9\end{array}}\\ \begin{array}{r}8\end{array}\end{array}$
$\begin{array}{r}\begin{array}{r}-\end{array}\underline{\begin{array}{r}30\\ 8\end{array}}\\ \begin{array}{r}22\end{array}\end{array}$