A box contains 20 machine parts, 5 of them being standard. A worker takes out 3 parts at random. Find the probability that at least 1 of 3 turns out to be standard.	Choose the correct choice from the following answers
A) 137/228
B) 13/228
C) 91/228
D) 41/228
E) None of these
Explanation :   Let, E ≡ at least 1 of the 3 parts turns out to be standard.   P(E) = 1 - P(none is standard)   = 1 - (15C3 / 20C3 ).   = 1 - (15 x 14 x 13) / ( 20 x 19 x 18).   = 137/228.   137/228nswer : 137/228
<result>A</result>
A box contains 20 machine parts, 5 of them being standard. A worker takes out 3 parts at random. Find the probability that at least 1 of 3 turns out to be standard.