Using proportions, it is found that:
A proportion is a fraction of total amount, and the measures are related using a rule of three.
For 40 servings:
The rule of three is:
1 oz yeast - 200 oz flour
0.35 oz yeast - x oz flour.
Applying cross multiplication:
[tex]x = 200(0.35) = 70[/tex]
70 ounces of flour are needed for 40 servings of bread and using 0.35 oz of yeast.
For 90 servings:
The rule of three is:
1 oz yeast - 180 oz flour
x oz yeast - 360 oz flour.
Applying cross multiplication:
[tex]2x = 360[/tex]
[tex]x = \frac{360}{2}[/tex]
[tex]x = 180[/tex]
180 ounces of yeast are needed for the 90 servings of bread using 360 oz of flour.
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