Answer:
3xyz
Step-by-step explanation:
The required sum = 7xyz+(−5xyz)+9xyz+(−8xyz)
=7xyz–5xyz+9xyz–8xyz
=(7–5+9–8)xyz
=(16–13)xyz
=3xyz
Answer:
Step-by-step explanation:
add 5. so thats -3x <-15
x is less than or equal to 5
Answer:
d
Step-by-step explanation:
1/9 as a decimal would be 0.111111
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)!)
