1. There were 11 yards mowed. Each yard is represented by an x on the line plot.
2. The most amount of gas used on any one yard was 5/8 of a gallon. The least amount of gas used was 1/8 of a gallon. The difference is (5/8)-(1/8)= (4/8)= 1/2 gallon
Answer:
a)
b) 
Step-by-step explanation:
Previous concepts
Normal distribution, is a "probability distribution that is symmetric about the mean, showing that data near the mean are more frequent in occurrence than data far from the mean".
The Z-score is "a numerical measurement used in statistics of a value's relationship to the mean (average) of a group of values, measured in terms of standard deviations from the mean".
Part a
Let X the random variable that represent the weights of a population, and for this case we know the distribution for X is given by:
Where
and
We are interested on this probability
And the best way to solve this problem is using the normal standard distribution and the z score given by:
If we apply this formula to our probability we got this:
And we can find this probability like this:
And in order to find these probabilities we can find tables for the normal standard distribution, excel or a calculator.
Part b
For this case we select a sample size of n =32. Since the distribution for X is normal then the distribution for the sample mean
is given by:
And the new z score would be:



Answer:
The solution is x=3 , y=-4 or (3,-4)
Step-by-step explanation:
Given equations (1 and 2) are:

To solve a system of equation with elimination method, the co-efficients of one of the variables has to be equated and then the equations are added or subtracted to get an equation in one variable.
Multiplying equation 1 by 2:

Multiplying equation 2 by 3

Adding equation 3 and 4

Putting y = -4 in equation 1

Hence,
The solution is x=3 , y=-4 or (3,-4)
Answer:
SinA=5/1 3 CosA=12/13 tanA=5/12. SinC=12/13 CosC=5/13 and tanC=12/5
Step-by-step explanation:
Basically find the third side by Pythagorean theorem which would get you 13. So 13 is the hypotenuse. Remember these 3 formulas. Sin=Opposite/Hypotenuse Cos=Adjacent/hypotenuse and Tan=opposite/Adjacent. So for Sin a the opposite side to angle A is 5. The hypotenuse is always the same which would be 13. So Sin a is 5/13. For cos the side adjacent would be 12. So it is 12/13. *Note Hypotenuse cannot be considered the adjacent.
Answer: B) reflection over the y-axis