Arrange the following from least to greatest: 12.718 x 10^7, 2.0 x 10^8, 80.618 x 10^6, 63,708,000, 0.00173615 x 10^11, 15,251 x 10^4

Alright, so we can multiply these out (for each power of 10, we move the decimal one spot to the right) to get

127,180,000

200,000,000

80,618,000

63,708,000

173,615,000

152,510,000

From here, we first look at the most digits in a number (9 in this case). Next, we look at the first digit in each number. If one is higher than all the rest, it is first. We then move to the next digit in the number until we're out of numbers with the maximum number of digits. We then repeat the process with the next highest number of digits, ending up with 200,000,000 as our highest number - I challenge you to do the rest on your own!