*Hint: In order to find the area of a rectangle you multiply the length and width.
Because the scale is 1:240, you multiply the sides by 240.
2.5 turns into 600.
2 turns into 480.
A = lw
A = (600)(480)
A = 288,000
The area would be 288,000 square feet.
To get the variance, start with finding the mean of your data points:
(23 + 19 + 22 + 30 + 28) / 5 = 24.4
Now take each data point and subtract the mean from it, then square that value:
23 - 24.4 = -1.4 * -1.4 = 1.96
19 - 24.4 = -5.4 * -5.4 = 29.16
22 - 24.4 = -2.4 * -2.4 = 5.76
30 - 24.4 = 5.6 * 5.6 = 31.36
28 - 24.4 = 3.6 * 3.6 = 12.96
Now get the average of those new numbers. That is your variance:
(1.96 + 29.16 + 5.76 + 31.36 + 12.96) / 5 = 16.24
The standard deviation will be the square root of the variance:
√(16.24) = 4.0299 (rounded to 4DP)
Answer:
C. 5
Step-by-step explanation:
3x – 7 > – 1
Add 7 to each side
3x – 7+7 > – 1+7
3x> 6
Divide each side by 3
3x/3 >6/3
x >2
X must be greater than 2
Answer:
set mary is x years old, and helen is y years old.
first sentence:x=2y
second one:4(y-8)=x+4
bring x=2y in 4(y-8)=x+4
=>4y-32=2y+4
=>2y=36
=>y=18
=>x=36
mary:36
helen:18