Answer:

Explanation:
There are only two mutually exclusive possibilities for each complex electronic system: being <em>defective</em> or being <em>not defective</em>:
- Number of complex electronic systems: 7
- Nmber of defective systems: 2
- Number of not defective systems: 5
<em>Probability </em>that no defective systems are found in the sample is the equal to the probability of selecting them consecutively without replacement and finding each one is not defective:
- Porbability the first is not defective × probability the second is not defective
- 5/7 × 4/6 = 20/42 = 10/21
30% percent is what they marked up
Answer: S= d/p
Step-by-step explanation: Take the distance (d) divided by time (t) and you should have your answer
Do you know the numbers a/b equals too