# Reliability

• Jun 8th 2010, 02:48 AM
shalini
Reliability

There are 16 components in a non redundant system.The average reliability by using a redundant system is 0.99. In order to achieve atleast this system reliability by using a redundant system with 4 identical new components, what should be the least reliability of each new component?
• Jun 8th 2010, 02:55 AM
SpringFan25
I assume that you are defining reliabiulity to be the chance of a system not failing within some time period.

In that case:

P(system doesn't fail) = p(at least 1 component works)
=1-P(all components fail)
=1-(1-r)^4

If there are 4 identical components with reliability r.

So just solve
$.99 =1-(1-r)^4$