To find the probability that a unit will pass inspection, we can determine the number of units that passed inspection and divide that by the total number of units inspected.
- Total units inspected = 500
- Units rejected (due to defects) = 80
- Units that passed inspection = Total units - Units rejected = 500 - 80 = 420
Now, we calculate the probability of passing inspection:
\[ \text{Probability of passing inspection} = \frac{\text{Units that passed}}{\text{Total units inspected}} = \frac{420}{500} \]
Calculating that gives:
\[ \frac{420}{500} = 0.84 \]
To express this as a percentage:
\[ 0.84 \times 100 = 84% \]
Thus, the probability that a unit will pass inspection (no defects) is 84%.