Let X Be the Time to Failure of an Electronic $E ( X ) = 4 \text { years }$

Short Answer

Let X be the time to failure of an electronic component, and suppose X is an exponential random variable with $E ( X ) = 4 \text { years }$ . Find the median lifetime, i.e., find M such that $\operatorname { Pr } ( X \leq M ) = \frac { 1 } { 2 }$ . Enter just a real number rounded to two decimal places (no units).