Just simple proportions:
12(apples) x(apples)
-------------- = --------------
4(oranges) 7(oranges)
12*7 = 84
84/4 = 21
There are 21 apples + 7 oranges = 28 apples and oranges!
1. The probability that we select a red marble is 1/3.
We found this out by taking the amount of red marbles there are and the total amount of marbles. The total amount of marbles is 18 and there are red marbles. So, it would become 6 out of 18 or 6/18. Then, we simplify 6/18 to the simplest form. The greatest common factor of both of those numbers is 6. Lastly, we divide each of them by 6 to get the simplest form.
6/18 = (6/6)/(18/6)
(6/6)/(18/6) = 1/3
So, therefore, the theoretical probability of picking a red marble is 1/3.
2. The probability that we select a blue marble is 2/3.
We can find this out by taking the amount of blue marbles there are and the total amount of marbles. We know that the total amount of marble is 18 and there are 12 blue marbles. So, we simply get the GCF (greatest common factor) and divide them by it.
Greatest Common Factor of 12 and 18 = 6
12/18 = (12/6)/(18/6)
(12/6)/(18/6) = 2/3
Thus, the theoretical probability of picking a blue marble is 2/3.
It would be biased because one would assume that students can get to school by means other than those that put them 8n the parking lor. (Parking lot = car drivers who would be the only students sampled.). Others may ride to school by either parent or school bus who could drop them off somewhere else or possibly walk to school. The freshmen/sophomores would be excluded generally as they would be too young to drive altogether
The final equation is:

Further explanation:
The general form of equation of a line in slope-intercept form is:

Here m is the slope
Given
m=1
(x,y) = (-7,-4)

To find the value of b, we have to put the point in the equation

The final equation is:

Keywords: Slope-intercept form, equation of line
Learn more about slope-intercept form at:
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