by solving a system of equations, we conclude that there are 7 students with blue eyes in the class.
We know that there are 40 students in the first-grade class, and we also know that:
Let's define the variables.
We know that:
H = 3*B
We also know that there are 3 students that have both blue eyes and blond hair.
And there are 15 students with none of these traits, so:
40 - 15 = 25
There are 25 students that have blue eyes, blond hair, or both.
Because we know that 3 students have both traits, we can write:
B + H - 3 =25
(Where we subtract 3 because we don't want to add these students twice).
Then we created a system of two equations:
H = 3*B
B + H - 3 =25
Replacing the first equation into the second one, we get:
B + (3*B) - 3 = 25
4*B = 25 + 3 = 28
B = 28/4 = 7
Then, by solving that system of equations, we conclude that there are 7 students with blue eyes in the class.
If you want to learn more about systems of equations:
https://brainly.com/question/13729904
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