First you would have to do 8 x 3, which is 24 because an octagon has 8 sides and it says with three times as large. Then you would do 24 x 50 cm2 which is 1,200 centimeters. And so the area would be 1,200 cenimeters. I don't know. But I am REALLY, REALLY, REALLY, REALLY, REALLY, REALLY, REALLY , REALLY, REALLY, REALLY, REALLY, REALLY, REALLY, REALLY, REALLY, REALLY, positive about my answer. Hope this helps! If anyone else answers it and the answer is different than mine, you can pick mine or theirs. :)