The type of graph that would allow us to quickly see how many students were treated would be a Bar graph.
If you have several different sized pizzas, you can compare their areas. So the area of a pizza is the length of the crust (circumference) divided by two times the distance from the edge to the middle (radius). Mathematicians use a special number called pi to calculate the circumference of a circle.
In order to find a fraction, We know that a percentage is out of a 100. This means we can now place our fraction as:
38/100
In order to find the actual fraction, we will want to simplify. Lets find our least common factor and work down from there. Since we know that 2 can go into both of them, lets reduce by 2.
This means our fraction will now look like:
19/50
Since 19 is a prime number and cannot be divided by anything but 1 and itself, we know that this is our simplified form.
This means:
19/50 is the fraction equivalent to 38%.