Answer:
455 or 680, depending
Step-by-step explanation:
If we assume the three choices are different, then there are ...
15C3 = 15·14·13/(3·2·1) = 35·13 = 455
ways to make the pizza.
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If two or three of the topping choices can be the same, then there are an additional ...
2(15C2) +15C1 = 2·105 +15 = 225
ways to make the pizza, for a total of ...
455 + 225 = 680
different types of pizza.
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There is a factor of 2 attached to the number of choices of 2 toppings, because you can have double anchovies and tomato, or double tomato and anchovies, for example, when your choice of two toppings is anchovies and tomato.
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nCk = n!/(k!(n-k)!)
Nikita's value is 4 times less than Bettina's value. I believe this is the answer.
Based on the reflexive property of congruency, the missing step in the proof is: A. ∠ABC ≅ ∠DBE
<h3>What is the
Reflexive Property of Congruency?</h3>
The reflexive property of congruency states that an angle will always be congruent to itself.
In the diagram given, we can prove that ∠ABC ≅ ∠DBE based on the reflexive property.
Therefore, the missing step in nthe proof is: A. ∠ABC ≅ ∠DBE
Learn more about reflexive property on:
brainly.com/question/1601404
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