Problem: The formula which expresses the relationship between and as shown in the accompanying table is:
Answer Choices:
A.
B.
C.
D.
E. none of the above formulae.
Solution:
To obtain a formula directly from the table involves work beyond the indicated scope. Consequently, the answer must be found by testing the choices offered. (A) is immediately eliminated since, for equally spaced values of , the values of are not equally spaced; cannot be a linear function of . (B) fails beyond the second set of values. (C) satisfies the entire table. (D) fails with the first set of values.