1/5+ (-4) is the same as 1/5 - 4
1/5-20/5
-19/5
Decrease because you taking something off of something
Answer:
<u>$4800</u>
Step-by-step explanation:
The expected net income is the probability when rains multiplied by net income (profit) summed with the probability of not raining with that days net income multiplied.
First, Chance of rain = 12% = 12/100 = 0.12
Profit/Loss = Income - Cost
Income is 5000
Cost = 9000
So,
Loss = 5000 - 9000 = 4000
Or, Net Income (profit) = - 4000
Now, Change of not raining = 100 - 12 = 88% = 88/100 = 0.88
Profit = Income - Cost
Income = 15,000
Cost = 9000
Net Income (profit) = 15000 - 9000 = 6000
So, we can write the expected net income as:
<u>Expected NI </u>= (0.12)(-4000) + (0.88)(6000) = <u>$4800</u>
Length = x + 2 (because it is 2 cm more than x)
Width = 2x - 5 (5 cm lest than 2x)Area = 54 cm2 this is the formula to find the area Length × Width = Area (x + 2)(2x - 5) = 542x2 - x - 10 = 54 (this is you area)
Subtract 54 on both sides of equation to make the right side zero. 2x2 - x - 64 = 0 then use the quadratic formula x = (-b ± √(b2 - 4ac)) / 2a where:a = 2b = -1c = -64 Plug in these values into the formula. x = (1 ± √(1 - 4(-128))) / 4 x = (1 ± √(513)) / 4 x = (1 ± 22.65) / 4 x = (1 + 22.65) / 4 and x = (1 - 22.65) / 4 x = 5.91 and x = -5.41 Check the validity of the x values by adding them to the length and width. If the length or width should be a negative value, then that value of x is not acceptable. Now x = 5.91 Length = 5.91 + 2 (positive value.)Width = 2(5.91) - 5 ( positive value.) x = 5.91 If we look at this -- x = -5.41, Both length and width will be negative values. We reject this value of x. The answer is x = 5.91
Hope I helped and sorry it was really long
Margin of error, e = Z*SD/Sqrt (N), where N = Sample population
Assuming a 95% confidence interval and substituting all the values;
At 95% confidence, Z = 1.96
Therefore,
0.23 = 1.96*1.9/Sqrt (N)
Sqrt (N) = 1.96*1.9/0.23
N = (1.96*1.9/0.23)^2 = 262.16 ≈ 263
Minimum sample size required is 263 students.
