John has 3 unique coins such that the probability of obtaining a head when the coin is flipped is 110, 210 and 310, respectively. If he flips each of the 3 coins once, the probability that at least 1 heads appears is p. What is the value of 1000p?

Answer 1

Your numbers are nuts, so I assume it should read 0.110, 0.210, 0.310 as the probabilities of Head.

pr(at least once)=1-pr(no heads)
= 1- (.890)(.790)(.690)=.515

1000p=515

Answer 2

496...............:)