Doubt in exponential distribution question.

Question

The amount of time that a surveillance camera will run without having to be reset is a random variable having the exponential distribution with mean 50 days. My question is

if $X$ is amount of time

1. $P$(camera have to reset in less than 20 days) is it $P(X<20)$ or $1-P(X<20)$?

2. $P$(no have to reset in atleast 60 days), is it $P(X>60)$ or $P(X<60)$?

Answer 1

If $X$~$exp(\frac{1}{50})$ is the time when the camera needs a reset (the exponentially distributed time) then $P(X<t)$ will be the probability that it will need a reset before time $t$.

Answer 2

"Amount of time that camera will run without having to be reset" = " camera will work from time $0$ to $<t$ and fail at time $t+dt$".
1 = failure within $20$ days = $P(X<20)$
2 = failure after $60$ days = $P(60 \leqslant X)=1-P(X<60)$