Answer:
1. E(Y) = 50.54°F
2. SD(Y) = 11.34°F
Step-by-step explanation:
We are given that The daily high temperature X in degrees Celsius in Montreal during April has expected value E(X) = 10.3°C with a standard deviation SD(X) = 3.5°C.
The conversion of X into degrees Fahrenheit Y is Y = (9/5)X + 32.
(1) Y = (9/5)X + 32
E(Y) = E((9/5)X + 32) = E((9/5)X) + E(32)
= (9/5) * E(X) + 32 { expectation of constant is constant}
= (9/5) * 10.3 + 32 = 50.54
Therefore, E(Y), the expected daily high in Montreal during April in degrees Fahrenheit is 50.54°F .
(2) Y = (9/5)X + 32
SD(Y) = SD((9/5)X + 32) = SD((9/5)X) + SD(32)
= * SD(X) + 0 { standard deviation of constant is zero}
= * 3.5 = 11.34°F
Therefore, SD(Y), the standard deviation of the daily high temperature in Montreal during April in degrees Fahrenheit is 11.34°F .
Given:
The table of values of a linear relationship.
x y
-1 -1
0 1
1 3
2 5
To find:
The equation for the given table of values.
Solution:
If a linear function passes through the two points, then the equation of the linear relationship is
Consider any two point from the given table. Let the two points are (-1,-1) and (0,1). So, the equation of the linear relationship is
Using distributive property, we get
Subtracting 1 from both sides, we get
Therefore, the required equation is . Hence, the correct option is D.
Answer:
- 2
Step-by-step explanation:
The sum of - 4 and - 15 = - 19
Increased by 17 means to add on 17 to the above result, that is
- 19 + 17 = - 2
Answer:
the value of x is 2
Step-by-step explanation:
Given the system
Cramer's rule has you compute 3 determinants, based on different matrices of the coefficients. We can call them A, B, C. Then x and y are found from their ratios.
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<em>Comment Cramer's Rule</em>
When the solution is some strange fraction, or when you only need one of the variable values (as here), Cramer's rule can get you there pretty directly.
The pattern of coefficient usage in Cramer's rule can be difficult to remember. If you swap the columns of each of the matrices, the pattern can be easier to remember, so that you can even do the math in your head.