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:
1. Her time in minutes is 720/s minutes
2. Given her time to be 20 minutes, her speed is 36 mph
Step-by-step explanation:
Mathematically,
Distance = speed * time
In this question, we want to calculate time;
So time = distance/speed
times = 12 miles/s mph = 12/s hours
Now we want our answer in minutes
Kindly recall that 60 minutes = 1 hour
So 12/s hours will be 12/s * 60 = 720/s minutes
2. Since she drives from home to the office in in 20 minutes, we want to calculate her speed in mph
From the time calculated above i.e 720/s
We can equate 20 = 720/s
20s = 720
s = 720/20
s = 36 mph
Answer:
Shoes for men
Step-by-step explanation:
Answer: the small bottle holds 15 ounces while the large bottle holds 23 ounces.
Step-by-step explanation:
Let x represent the number of ounces that a small bottle holds.
Let y represent the number of ounces that a large bottle holds.
He drank 2 small bottles and 2 large bottles, for a total of 76 ounces. It means that
2x + 2y = 76 - - - - - - - - - - - - 1
The day before, he drank 4 small bottles and 1 large bottle, for a total of 83 ounces. This means that
4x + y = 83 - - - - - - - - - - - - -2
Multiplying equation 1 by 2 and equation 2 by 1, it becomes
4x + 4y = 152
4x + y = 83
Subtracting, it becomes
3y = 69
y = 69/3 = 23 ounces
Substituting y = 23 into equation 1, it becomes
2x + 2 × 23 = 76
2x + 46 = 76
2x = 76 - 46 = 30
x = 30/2 = 15 ounces
Answer:
ferris wheel travel approx = 434.72 ft
Step-by-step explanation:
given data
wheel rotates = 9pi/8 radians
total height of the ferris wheel = 246 ft
solution
we can say here that height of the ferris wheel is same as the diameter of the wheel
and wheel is circular in shape
so we get here first radius of wheel that is
radius = half of diameter ..........................1
put here value and we get
radius = 0.5 × 246
radius = 123 ft
and
wheel travel distance = length of arc by a angle of wheel rotates
so here length of arc will be
arc length = radius × wheel rotates angle .....................2
put here value and we get
arc length = 123 ×
arc length = 434.7178 ft
so ferris wheel travel approx = 434.72 ft