Answer:
μ = 235.38
σ = 234.54
Step-by-step explanation:
Assuming the table is as follows:
![\left[\begin{array}{cc}Savings&Frequency\\\$0-\$199&339\\\$200-\$399&86\\\$400-\$599&55\\\$600-\$799&18\\\$800-\$999&11\\\$1000-\$1199&8\\\$1200-\$1399&3\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bcc%7DSavings%26Frequency%5C%5C%5C%240-%5C%24199%26339%5C%5C%5C%24200-%5C%24399%2686%5C%5C%5C%24400-%5C%24599%2655%5C%5C%5C%24600-%5C%24799%2618%5C%5C%5C%24800-%5C%24999%2611%5C%5C%5C%241000-%5C%241199%268%5C%5C%5C%241200-%5C%241399%263%5Cend%7Barray%7D%5Cright%5D)
This is an example of grouped data, where a range of values is given rather than a single data point. First, find the total frequency.
n = 339 + 86 + 55 + 18 + 11 + 8 + 3
n = 520
The mean is the expected value using the midpoints of each range.
μ = (339×100 + 86×300 + 55×500 + 18×700 + 11×900 + 8×1100 + 3×1300) / 520
μ = 122400 / 520
μ = 235.38
The variance is:
σ² = [(339×100² + 86×300² + 55×500² + 18×700² + 11×900² + 8×1100² + 3×1300²) − (520×235.38²)] / (520 − 1)
σ² = 55009.7
The standard deviation is:
σ = 234.54
To divide by a fraction is to multiply by its recipricle.
3/7 × 2/1
simplify fraction
3/7 × 2
multiply
6/7
Answer:
Ana still needs to read 1/5 of th journal
Hello! I'll write the instructions to graph these functions.
f(x)=x
Technically, this function is y=x, so the slope would be 1. To graph this one, start at the origin (0,0) and move up one unit, and to the right one unit since this is a positive slope.
g(x)= -1/3x+2
First, plot a point at y=2 when x=0. 2 is your y-intercept. Your slope is negative, so the line will be decreasing. From your first point, head down 1 unit and to the right 3 units. Continue plotting points from the previous points.
Also, if you have a graphing calculator, here are the steps to graphing the functions: ON, Y= (enter your functions), and press GRAPH or 2nd, TABLE to see individual points. Hope this helps! :)
Answer:
6 chairs
8 desks
Step-by-step explanation:
First, we assume that all 14 items he bought were chairs, if that was to be true then the office manager would spend...
125 x 14 = 1750$
We see that he spent less then he should have so now we start to substitute desks instead of chairs, and we have to keep in mind that if we change 1 chair to a desk then the total will increase by...
515 - 125 = 390$
Now we just find the difference between the needed total and the total that we get if the office manager would by only chairs and then divide the result by 390 in order to find the number of desks, and so we get...
(4870 - 1750) / 390 = 3120 / 390 = 8 desks
And now that we know the number of desks we just subtract the number of desks from 14 and get the number of chairs, and so...
14 - 8 = 6 chairs
