Let h be the number of heads and t be the number of tails obtained.
The total points obtained is 10h+5t.
For the man to get exactly 30 points, we must have:
10h+5t=30⇒2h+t=6
Since h and t are non-negative integers, the possible pairs of (h,t) are (3,0), (2,2), (1,4), and (0,6).
For each pair, the number of possible sequences of heads and tails is given by h+tCh, and the probability of any specific sequence is (21)h+t.
The total probability is the sum of the probabilities of all these mutually exclusive cases:
For h=3,t=0, the probability is 3C3(21)3=1×81=648.
For h=2,t=2, the probability is 4C2(21)4=6×161=6424.
For h=1,t=4, the probability is 5C1(21)5=5×321=6410.
For h=0,t=6, the probability is 6C0(21)6=1×641=641.
Total probability =648+6424+6410+641=6443.
Thus, m=43 and n=64.
Since gcd(43,64)=1, the fraction is in its simplest form.
m+n=43+64=107.
Answer: 107