What is the version number indicated by the following 4 bytes little endian in hexadecimal format: 10000000?
Remember, the least significant byte appears first. Let's reverse it so we can do the base math we're familiar with:
00 00 00 10
And here's the math:
0*16^7 + 0*16^6 + 0*16^5 + 0*16^4 + 0*16^3 + 0*16^2 + 1*16^1 + 0*16^0
So, the version number is 16! Maybe one day Bitcoin transactions will get there!