Final answer:
The incorrect statement is b. x + z < y.
Step-by-step explanation:
Let's evaluate each statement using the given values:
a. x + y > z
Substituting the values of x, y, and z, we get 3 + 7.1 > 11.5, which is true.
b. x + z < y
Substituting the values of x, y, and z, we get 3 + 11.5 < 7.1, which is false.
c. y - z < x
Substituting the values of x, y, and z, we get 7.1 - 11.5 < 3, which is false.
d. x . y = z
Substituting the values of x, y, and z, we get 3 . 7.1 = 11.5, which is false.
Therefore, the incorrect statement is b. x + z < y.