i would say that he divided each rectangle in 12 identical parts for the first rectangle he shaded 1/3 of 12 = 4 parts for the second rectangle he shaded 1/4 of 12= 3 parts
so 12= 3*4 leads to a minimum of 12 parts :)
1/4 of 12. 12 parts ;
The least number of parts into which both rectangles could be divided is 12. This is found by determining the least common multiple of the denominators of the fractions that were shaded, which are 3 and 4. The LCM of 3 and 4 is 12, allowing equal divisions for both shaded areas.
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