Question

A company makes molded plastic toys. In‑house researchers study the plastic injection process to determine what causes variations. A special cause of variation is:

a)the exact temperature of the injected plastic.

b)a small clog on the machine’s injector ports.

c)a new supplier of the raw plastic.

Answer 1

CHARACTERISTICS OF SPECIAL CAUSE OF VARIATION:

Here, Options a) the exact temperature of the injected plastic and b) a small clog on the machine’s injector ports are COMMON CAUSES OF VARIATION i.e they are expected, predictable and normal in the plastic injection process.

But, Option c) a new supplier of the raw plastic is Unexpected and Unpredictable i.e a SPECIAL CAUSE VARIATION.

Hence, Option c) a new supplier of raw plastic is the CORRECT ANSWER.