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.
Yes the product of two integers with different sings can be positive or negative if is negative and negative equal a positive
Answer:

Step-by-step explanation:
We can apply the distributive property then combine like terms for a simpler equation.

Hope this helped!
Answer: The original price of brownie was $2.1 each.
Step-by-step explanation:
since we have given that
Let the original price will be x
Number of brownie purchased = 8
According to question , each brownie costs $0.20 less than the original price.
So, it becomes

Hence, the original price of brownie was $2.1 each.
The question doesn't seem specific enough. If there are options, please list.