Answer:
A student had a hypothesis for a science project. He believed that the more students studied math, the better their math scores would be. He took a poll in which he asked students the average number of hours that they studied per week during a given semester. He then found out the overall percent that they received in their math classes. His data is shown in the table below:
Study Time (hours) 4 3.5 5 2 3 6.5 0.5 3.5 4.5 5 1 1.5 3 5.5
Math Grade (percent) 82 81 90 74 77 97 51 78 86 88 62 75 70 90
In order to understand this data, he decided to make a scatterplot.
The independent variable, or input data, is the study time because the hypothesis is that the math grade depends on the study time. That means that the math grade is the dependent variable, or output data. The input data is on the x-axis and the output data is on the y-axis.
The scales and intervals on the axes will be determined by the data. Since the greatest value on the x-axis is 6.5, you can use intervals of 1 until you reach 7. On the y-axis, the greatest value is 97 and, since it is a percent, you can use intervals of 10 until you reach 100.
Step-by-step explanation:
Now you can graph the points on the scatterplot. In order to plot the points, you will show each one as an ordered pair (hours, percent). The first ordered pair, then, is (4, 82). Plot each of the 14 points. Remember, it takes two pieces of data to make a single point.
You can see that there is a relationship between the independent and dependent values of the chart.
Scientists in the real world rarely create scatterplots on a piece of paper and compute equations by hand. They use computer programs that can approximate the trend line much more accurately.
You can make scatterplots on your graphing calculator, if you have one. Then, you can compute the trend line called the linear regression in some models. Your graphing calculator can put the equation in y=mx+b form or Ax+By=C form, depending on the mode you choose. Then, you can choose any input values for which your calculator will tell you the output values.
