I think the answer is 2774, it's just a case of adding up all the numbers from 2 to 74. It's like flip 1 and 2, could be the only 2 tails, then 1 and 3, 1 and 4 etc up to 1 and 75, then 2 and 3, 3 and 4 etc.... U get what I mean, anyway I think it's 2774
