At a school, 129 students play at least one sport. This is 30% of the students at the school. How many students are at the sc
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Answer:
There are 3478761 ways to select the first 5 numbers
Step-by-step explanation:
As understood from the statement of this problem we assume that it does not matter the order in which the first 5 white balls are selected.
In this case it is a combination.
So, what we want to know is how many ways you can choose 5 white balls out of 55.
Then we use the formula of combinations:
Where you have n elements and choose x from them.
Then we look for:
The function is divided in 2 parts:
For x<0, the function is
, which is a linear function, and its graph is a line.
For x≥0, the function is
, which is a quadratic function, and its graph is a parabola.
Note that y=x is the line containing the points (0, 0), (1, 1), (5, 5) etc, that is, it is the line passing through the origin, with an inclination of 45° with the positive x-axis.
The parabola is the parabola 
reflected with respect to the x-axis. It contains points like (0, 0), (-1, 1), (2, -4) etc...
The 2 graphs, with domain all real numbers, are shown in the first picture.
The second picture is the graph of the function described in our problem. We use the first picture, but restrict the domains.
That is, we delete the part of the line corresponding to x≥0, and the part of the parabola corresponding to x<0.
For x<0, the function is
For x≥0, the function is
Note that y=x is the line containing the points (0, 0), (1, 1), (5, 5) etc, that is, it is the line passing through the origin, with an inclination of 45° with the positive x-axis.
The parabola
The 2 graphs, with domain all real numbers, are shown in the first picture.
The second picture is the graph of the function described in our problem. We use the first picture, but restrict the domains.
That is, we delete the part of the line corresponding to x≥0, and the part of the parabola corresponding to x<0.