Answer:
68 weeks
Step-by-step explanation:
1 week costs $11.50.
so, how many such weekly each cycles fit into the price of new machines ?
if they wait to long (to many weeks) they spend in total more money than buying a new machine.
but if they stay still below that max. number of weeks, they have at least the illusion that they are cheaper of with the weekly laundromat investment (but they forget, sooner or later they will need the new machines).
so the break even point is simply
782 / 11.5 = 68 weeks.
after 68 weeks it has cost them exactly the same amount of money, as if they had bought new machines right away at the beginning.
Answer:
Csc(pi)
Cot(pi)
Csc(0)
Sec(90)
Step-by-step explanation:
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)!)
