Find the nth term of... 3,1,-1,-3...a. 5n-2b. 3n+5c. 5n+3d. -2n+5
2 answers:
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ANSWER: 32 five-dollar bills
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EXPLANATION:
Let x be number of $5 bills
Let y be number of $10 bills
Since we have total of 38 bills, we must have the sum of x and y be 38
x + y = 38 (I)
Since the total amount deposited is $220, we must have the sum of 5x and 10y be 220 (x and y are just the "number of" their respective bills, so we multiply them by their value to get the total value):
5x + 10y = 220 (II)
System of equations:
Divide both sides of equation (II) by 5 so our numbers become smaller
Rearrange (I) to solve for y so that we can substitute into (II)
Substituting this into equation (II) for the y:
We have 32 five-dollar bills
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If we want to finish off the question, use y = 38 - x to figure out number of $10 bills
32 five-dollar bills and 6 ten-dollar bills
This question is incomplete, in that the Excel File: data07-11.xlsx a. was not provided, but I was able to get the information on the Excel File: data07-11.xlsx a. from google as below:
57 61 86 74 72 73
20 57 80 79 83 74
The image of the Excel File: data07-11.xlsx a. is also attached below.
Answer:
a) Point estimate of sample mean = 68
b) Point estimate of standard deviation (4 decimals) = 17.8122
Step-by-step explanation:
a) Point estimate of sample mean, \bar{x} = ∑Xi / n = (57 + 61 + 85 + 74 + 73 + 72 + 20 + 58 + 81 + 78 + 84 + 73)/12 = 68
b) Point estimate of standard deviation = sqrt ∑ Xi² - n\bar{x}² / n-1)
= sqrt(((57 - 68)^2 + (61 - 68)^2 + (85 - 68)^2 + (74 - 68)^2 + (73 - 68)^2 + (72 - 68)^2 + (20 - 68)^2 + (58 - 68)^2 + (81 - 68)^2 + (78 - 68)^2 + (84 - 68)^2 + (73 - 68)^2)/11) = 17.8122
