math
posted by audrey .
ther are 33 students in the band. there are 6 more fifthgrade students than thirdgrade students. there are an equal number of third and fourthgrade students.how many thirdgrade students are in the band?

x =# fifth grade students.
y = # fourth grade students
z = # third grade students.
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x + y + z = 33
x = z + 6
y = z
Solve for x, y, z.