A box contains seven bulbs out of which 4 are defective. If four bulbs are chosen at random, find the probability that at least one bulb is good? Pick:
A) 2045/2401
B) 2121/2401
C) 2145/2401
D) 2345/2401
E) 2245/2401
Required probability   = 1 - 256/2401   = 2145/2401   Answer: 2145/2401
<result>C</result>
A box contains seven bulbs out of which 4 are defective. If four bulbs are chosen at random, find the probability that at least one bulb is good?