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)!)
2%
take the absolute value of your (experimental-accepted then divide by the accepted) so (20-25)/25=.2
then multiply that number by 100 to get the percent, .2*100=2
Let n be the amount of time it takes william to cut the lawn. Then Shelly takes
n-2 hours. So:
1/n+1/n-2=1/3
3(n-2)+3n=n²-2n
6n-6=n²-2n
n²-8n+6=0
Using the quadratic formula, we get a positive value of 7.1623 hrs as the amount of time william takes working alone, and 5.1623 as the amount of time Shelly takes working alone
☺☺☺☺
First, you need to change it from standard form to slope-intercept form. To do this, you have to add 3x to both sides. Now that y is by itself, divide by 5 on both sides. Your equation should now be y=3x+3. Then, graph the points. Your x-intercept should be at (-5,0) and your y- intercept should be at (0,3).
