Keep in mind both the distance and time of the scenarios. The faster and more distance travelled = a higher gradient for the line. If he slows, the gradient decreases. If he stops, the line is flat but time still goes on.
Answer:
0.675
Step-by-step explanation:
27/40
- Divide each number by 10
2.7/4
- Multiply each number by 25
67.5/100
Convert that into a decimal. :)
Let Xi be the random variable representing the number of units the first worker produces in day i.
Define X = X1 + X2 + X3 + X4 + X5 as the random variable representing the number of units the
first worker produces during the entire week. It is easy to prove that X is normally distributed with mean µx = 5·75 = 375 and standard deviation σx = 20√5.
Similarly, define random variables Y1, Y2,...,Y5 representing the number of units produces by
the second worker during each of the five days and define Y = Y1 + Y2 + Y3 + Y4 + Y5. Again, Y is normally distributed with mean µy = 5·65 = 325 and standard deviation σy = 25√5. Of course, we assume that X and Y are independent. The problem asks for P(X > Y ) or in other words for P(X −Y > 0). It is a quite surprising fact that the random variable U = X−Y , the difference between X and Y , is also normally distributed with mean µU = µx−µy = 375−325 = 50 and standard deviation σU, where σ2 U = σ2 x+σ2 y = 400·5+625·5 = 1025·5 = 5125. It follows that σU = √5125. A reference to the above fact can be found online at http://mathworld.wolfram.com/NormalDifferenceDistribution.html.
Now everything reduces to finding P(U > 0) P(U > 0) = P(U −50 √5125 > − 50 √5125)≈ P(Z > −0.69843) ≈ 0.757546 .
Answer:
7/8
Step-by-step explanation:
Before we do this problem, let's go over a little algebra terminology.
The number in front of your variable is called your <em>coefficient </em>and notice that the <em>x</em> at the end of the problem does not have a coefficient.
When that happens, when there is no number in front of your variable, you can put a 1 there to fill that position. So -x can be thought of as -1x.
Next let's change all our minus signs to plus negatives.
So the problem reads 3x + 5 + 7x + -3 + -1x + 2.
Now let's simplify this by combining like terms.
We can combine our "x" terms first.
3x + 7x + -1x simplifies to +9x.
Now, 5 + -3 + 2 simplifies to 4.
So our answer is 9x + 4.
