Posted by **Tony ** on Wednesday, June 8, 2011 at 7:56pm.

A machine has 7 identical components which function independently. The probability that a component will fail is .2. The machine will stop working if more than three components fail. Find the probability that the machine will be working?

- Elementary Statistics -
**Reiny**, Wednesday, June 8, 2011 at 8:21pm
The machine will be working if

1. no part fails ---> (.8)^7

2. 1 part fails ----> C(7,1)(.2)(.8)^6

3. 2 parts fail ---> C(7,2)(.2^2)(.8^5)

4. 3 parts fail ---> C(7,3)(.2^3)(.8^4)

add them up

## Answer this Question

## Related Questions

- discrete probability distribution (help please!) - a machine has 7 identical ...
- stat - a machine has 7 identical components which function independently. the ...
- problem solving - for a parallel structure of identical components, the system ...
- Maths - a missile guidance system has five fail-safe components. the probability...
- Statistics - A certain airplane has two independent alternators to provide ...
- statistics - A certain airplane has two independent alternators to provide ...
- math - A machine has four components, A, B, C, and D, set up in such a manner ...
- Math - A company that produces a particular machine component has 3 factories, ...
- Math - A company that produces a particular machine component has 3 factories, ...
- statistics - I cant figure this out, please explain. A certain airplane has (2) ...

More Related Questions