Question

Which expression represents 92 decreased by an unknown number?

A.
92 ÷ z

B.
92 + z

C.
92 z

D.
92 – z

Answer 1

D.92-z because you are subtracting which is decreasing 

Answer 2

D shows 92 decreased by an unknown number
the unknown number is replaced by a variable. In this equation the variable is Z.