-8 = trevon
(3/4)-8 = beth
= -6
1/4[(3/4)-8] = leah
1/4(-6)
= -1.5
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
Answer:
Step-by-step explanation:
D
Answer:
x=175
Step-by-step explanation:
The sum of all the degrees in a triangle is 180. First, you have to rind what the third degree of the triangle is. We will call this y.
85+90+y=180
175+y=180
y=5
The floor is flat, so it will be 180 degrees, therefore, x+y=180. We can substitute 5 in for y, so 5+x=180.
So, x would be 175.
Let's solve your system by substitution.
−3x+y=−2;y=4x
Rewrite equations:
y=4x;−3x+y=−2
Step: Solvey=4xfor y:
y=4x
Step: Substitute4xforyin−3x+y=−2:
−3x+y=−2
−3x+4x=−2
x=−2(Simplify both sides of the equation)
Step: Substitute−2forxiny=4x:
y=4x
y=(4)(−2)
y=−8(Simplify both sides of the equation)
Answer:
x=−2 and y=−8