1967 AMC 12 Question 9
AMC12 · 1967 AMC 12
Let $K,$ in square units, be the area of a trapezoid such that the shorter base, the altitude, and the longer base, in that order, are in arithmetic progression. Then:
$K$ must be an integer
$K$ must be a rational fraction
$K$ must be an irrational number
$K$ must be an integer or a rational fraction
taken alone neither $(A)$ nor $(B)$ nor
$(C)$ nor $(D)$ is true