146 minutes ;
2 x 10 (classes x mins to take) = 20mins
21 x 2 = 42 individual students (students per class x number of classes) 42 x 3 (students x mins to take) = 126mins
20 + 126 = 146 minutes (2 hours and 26 minutes)
It will take approximately 146 minutes, or 2 hours and 26 minutes, to take both individual and class pictures for the two classes. This is calculated by adding the time for class pictures and individual pictures together. Specifically, 20 minutes for class pictures and 126 minutes for individual pictures.
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