I am stuck from here. I keep getting numbers that don't make sense.
We are unable to see what you're actually doing to arrive at numbers that don't make sense, so how can we determine what you've done incorrectly?
Your Venn diagram looks good, to me.
Now it's time to write some equations.
As Jeff suggested, we define symbols for unknowns first. (Otherwise, how could we write down unknown numbers?)
d = number of students who only know Dutch
p = number of students who only know Polish
t = number of students who only know Turkish
How many students know Polish? Look at your circle P and add them up:
p + 27 + 13 + 37
We see that
p + 77 students know Polish.
Follow the same reasoning, to express the number of students who know Dutch.
An equal number of students know Polish and Dutch, so we may write:
p + 77 = d + 57
Keep going; use symbol t as well.
There is also an equation that you may write that involves the number 200. Can you figure out that equation?
You now have a system of equations involving three symbols. Solve for symbol p because that's what the exercise asks for.
Let us know, if you get stuck again.
Cheers :cool: