    #### 1.    23 × 97 =

(a) write the multiplication as follows:

 23 ×    97 -------
(b) multiply 23 by 7:
 23 ×    97 ------- 161
(c) multiply 23 by 90:
 23 ×    97 ------- 161 2070 -------
(d) add the two resulting rows:
 23 ×    97 ------- 161 +2070 ------- 2231

#### 2.    475 × 88 =

(a) write the multiplication as follows:

 475 ×    88 -------
(b) multiply 475 by 8:
 475 ×    88 ------- 3800
(c) multiply 475 by 80:
 475 ×    80 ------- 3800 38000 -------
(d) add the two resulting rows:
 475 ×    88 ------- 3800 +38000 ------- 41800

#### 3.    576 × 72 =

(a) write the multiplication as follows:

 576 ×    72 -------
(b) multiply 576 by 2:
 576 ×    72 ------- 1152
(c) multiply 576 by 70:
 576 ×    72 ------- 1152 40320 -------
(d) add the two resulting rows:
 576 ×    72 ------- 1152 +40320 ------- 41472

#### 4.    1783 × 37 =

(a) write the multiplication as follows:

 1783 ×    37 -------
(b) multiply 1783 by 7:
 1783 ×    37 ------- 12481
(c) multiply 1783 by 30:
 1783 ×    37 ------- 12481 53490 -------
(d) add the two resulting rows:
 1783 ×    37 ------- 12481 +53490 ------- 65971

#### 5.    684 × 47 =

(a) write the multiplication as follows:

 684 ×    47 -------
(b) multiply 684 by 7:
 684 ×    47 ------- 4788
(c) multiply 684 by 40:
 684 ×    47 ------- 4788 27360 -------
(d) add the two resulting rows:
 684 ×    47 ------- 4788 +27360 ------- 32148

#### 6.    786 × 77 =

(a) write the multiplication as follows:

 786 ×    77 -------
(b) multiply 786 by 7:
 786 ×    77 ------- 5502
(c) multiply 786 by 70:
 786 ×    77 ------- 5502 55020 -------
(d) add the two resulting rows:
 786 ×    77 ------- 5502 +55020 ------- 60522 back to:    