Question

Three hundred high school seniors were surveyed about their intended college majors. The results are displayed in the Venn Diagram below: {see image.}
If a student is randomly selected from the group, what is the probability that they are majoring in both math and science? Round your answer to the nearest whole percent.

10%
17%
33%
40%

Answer 1

The probability is 10% (You have to add all the values given which equals 270, then you subtract 270 from the total which is 300, finally you divide the difference by the total so 30/300. That equals 10%

Answer 2

In total, the numbers in this venn diagram would add up to 300. We first need to find the missing number for how many seniors said they were majoring in both math and science.

300 = 120 + x + 50 + 100

300 = x + 270

x = 30

Now that we know the missing number, we can find the probability that a high school senior is majoring in both math and science. The probability would be majoring in both divided by all high school seniors in the sample.

30 / 300 = 1 / 10

10%

Hope this helps! :)