70 miles , 333.15km , average speed 112 kilometers/hours
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)!)
<span>The answer is c. 1.5r + 2.5(5 – r) = 10.50. Let r be the number of raisins and p be the number of peanuts. Raisins cost $1.50 per pound: 1.5r. Peanuts cost $2.50 per pound: 2.5p. Jeremy spends $10.50: 1.50r + 2.50p = 10.50. Jeremy makes 5 pounds of trail mix: r + p = 5. So, we have the system of two equations: 1.5r + 2.5p = 10.50 and r + p = 5. Use the second equation to express p: p = 5 - r. Now, substitute p in the first equation: 1.5r + 2.5(5 - r) = 10.50. Therefore, the correct choice is c. 1.5r + 2.5(5 – r) = 10.50.</span>
