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Why are we counting above days marked in red as different?iamseer wrote:R = rain
N = no rain
possibilities for at least 3 consecutive days:(Rains for 5 or 4 or 3 consecutive days)
RRRRR = (1/2)^5 =1/32
NRRRR = (1/2)^5 =1/32
RRRRN = (1/2)^5 =1/32
RRRNN = (1/2)^5 =1/32
NRRRN = (1/2)^5 =1/32
NNRRR = (1/2)^5 =1/32
RRRNR = (1/2)^5 =1/32
RNRRR = (1/2)^5 =1/32
IMO answer 1/4
Because they are 2 different arrangements. If you were to write out all 32 possible arrangements, you would find that 1/4 of them (or, 8 of them as this_time_i_will showed) would have at least 3 consecutive "R"s. Those are 2.Why are we counting above days marked in red as different?
