Answer: You can see if the graphs of the two populations meet at a given point.
Step-by-step explanation:
If we have a graph of population vs time
such that y = population and x = time, two different populations will be exactly the same for a given time if we have an intersection of the two graphs. The value (x0, y0) where the graphs cross is the time = x0 and the population y0, this means that both populations have y0 individuals at the same time.
Remmeber you can do anything to an equaiton as long as you do it to btoh sides
5-6(a+2)=7+a
distribute
5-6a-12=7+a
add like terms
-6a-7=7+a
add 6a both sides
-7=7+7a
minus 7 both sides
-14=7a
divide by 7
-2=a
a=-2
Answer: C. 180 times
Step-by-step explanation:
From the 60 trials, the percentage of times Laura picked a green marble was:
= 100% - Percentage of times blue and red were picked
= 100% - 25% - 15%
= 60%
If these results were repeated with 300 trials, the number of times Laura would be expected to pick green would be:
= 60% * 300
= 180 times
Answer: 3/4 inch
Step-by-step explanation:
When Jim was 15, he grew 1/4 of an inch and when he was 16, he grew 1/2 of an inch.
His growth during those two years will be:
= 1/4 + 1/2
= 1/4 + 2/4
= 3/4 inch
His growth increased by 3/4 inches.
To get the z-value of the scores of the four students, we are going to use the formula for standard score or z-score. It is score minus the mean score, then divided by standard deviation.
z= Score (X)-Mean / SD
To find the z-value of each score, we have to use a Z table. Using the z-score, we are to look first at the y-axis of the table which will highlight the first two digits of the z-score. Then, the x-axis for the second decimal place of the z-score.
You can use this as reference for the z-table: http://www.stat.ufl.edu/~athienit/Tables/Ztable.pdf
Mean= 500SD= 100Scores= 560, 450, 640, 530
For the student who scored 560,z= X-Mean / SDz= 560-500 / 100z= 60 / 100z= 0.6
The score is 0.6 standard deviation above the mean. The z-value is 0.7257 or 72.57%.
For the student who scored 450,z= X-Mean / SDz= 450-500 / 100z= -50 / 100z= -0.5
The score is -0.5 standard deviation above the mean. The z-value is 0.3085 or 30.85%.
For the student who scored 640,z= X-Mean / SDz= 640-500 / 100z= 140 / 100z= 1.4
The score is 1.4 standard deviation above the mean. The z-value is 0.9192 or 91.92%.
For the student who scored 530,z= X-Mean / SDz= 530-500 / 100z= 30 / 100z= 0.3
The score is 0.3 standard deviation above the mean. The z-value is 0.6179 or 61.79%.
