Step 1: Write down the binary number:
100001111
Step 2: Multiply each digit of the binary number by the corresponding power of two:
1x28 + 0x27 + 0x26 + 0x25 + 0x24 + 1x23 + 1x22 + 1x21 + 1x20
Step 3: Solve the powers:
1x256 + 0x128 + 0x64 + 0x32 + 0x16 + 1x8 + 1x4 + 1x2 + 1x1 = 256 + 0 + 0 + 0 + 0 + 8 + 4 + 2 + 1
Step 4: Add up the numbers written above:
256 + 0 + 0 + 0 + 0 + 8 + 4 + 2 + 1 = 271.
So, 271 is the decimal equivalent of the binary number 100001111.
FINAL ANSWER:
[tex]\huge\orange{\boxed{decimal. : 271}}[/tex]