Find the probability of 0 heads, 1 head, 2 heads, ..., 6 heads. Then multiply by 200.
For example, the probability of 2 heads = .6^2 * .4^4 * 6!/(2!4!)
where .6^2 is the probability of getting 2 heads, and .4^4 is the probability of getting (since you're doing 6 flips) 4 tails, and 6!/(2!4!) is the number of orderings of 2 heads & 4 tails; in 6 flips, the number of orderings of H heads = 6!/(H! (6-H)!)





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