Answer:
The probability that the next room will require less than 32 minutes to clean
0.222222 = 22.22%
The probability that the next room will require more than 30 minutes to clean.
0.833333 = 83.33%
The mean
36.5
Standard deviation of the distribution
26.92
Step-by-step explanation:
Total Probable Outcomes = 18
Event 1
Possible outcomes less than 32 = 32-28 = 4
Probability less than 32 = 4/18 = 2/9 = 0.222222
Event 2
Possible outcomes less than 32 = 45-30 = 15
Probability less than 32 = 15/18 = 5/6 = 0.833333
Mean
Mean = (28+29+30+31+32+33+34+35+36+37+38+39+40+41+42+43+44+45)/18 = 36.5
Standard deviation of the distribution
*MS Excel file is attached for solution.
For the answer to the question above, I'll show my solution for the answer below.
Area A = pi r^2
<span>The rate of change of area = d A/ d t = 2 pi r d r/d t </span>
<span>r= 2t, d r = 2 d t </span>
<span>This gives </span>
<span>d A/ d t = 2 pi 2t 2 d t = 8 pi t dt </span>
<span>Integrate it </span>
<span>A= 4 pi t^2. </span>
<span>After t=5, the area will be 100* 3.14 square= 314 square units.</span>
Simplify brackets
2/5(x - 4) = 2x
Simplify 2/5(x - 4) to 2(x - 4)/5
2(x - 4)/5 = 2x
Multiply both sides by 5
2(x - 4) = 10x
Divide both sides by 2
x - 4 = 5x
Subtract x from both sides
-4 = 5x - x
Simplify 5x - x to 4x
-4 = 4x
Divide both sides by 4
-1 = x
Switch sides
<u>x = -1</u>
