The Microprocessors, Which Are Used in Automobiles to Regulate Fuel

Multiple Choice

The microprocessors, which are used in automobiles to regulate fuel consumption, are guaranteed against defects for 20,000 miles of use. Tests conducted in the laboratory under simulated driving conditions reveal that the distances driven before the microprocessors break down are exponentially distributed and that the average distance driven before the microprocessors fail is 120,000 miles. What is the probability that a microprocessor selected at random will fail during the warranty period?

A) 0.15
B) 0.12
C) 0.36
D) 0.63
E) 0.85