Using proportions, it is found that 66 men can leave so there will still be enough food.
A proportion is a fraction of a total amount, and the measures are related using a rule of three.
Considering the situation described, the rule of three is given as follows:
4200 men - 32 days - 12 hectogram per person.
x men - 42 days - 16 hectogram per person.
Considering that the amount per person and the number of people is inverse proportional, we have that:
[tex]\frac{4200}{x} = \frac{32}{42} \times \frac{16}{12}[/tex]
[tex]\frac{4200}{x} = \frac{512}{504}[/tex]
Applying cross multiplication:
512x = 504 x 4200
x = 504 x 4200/512
x = 4134.
The amount of men that can leave is:
4200 - 4134 = 66.
More can be learned about proportions at https://brainly.com/question/24372153
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