Step-by-step explanation
The probability that Event A happening is the following:

The probability of Event A not happening is the following:

Therefore, we have:

Plugging in the terms into the expression:
1.8 + P(Not malfunctioning) = 100%
Subtracting -1.8 to both sides:

Subtracting numbers:

In conclusion, the probability of not malfunctioning is 0.982