Ok, step by step answer.
Step 1: Move the decimal over so that no visible decimals remain. REMEMBER: you must move the decimal the same amount of places in both numbers - ALWAYS. Luckily, both of these numbers only have one decimal place, so we move the decimal over, turning the problem into: 905 ÷ 73.
Step 2: Divide using a calculator or long division. Start with the first 2 digits, 90 divided by 73. 73 goes into 90 1 time, so put a 1 at the top of the division box and subtract 73 from 90. Take the difference between the 2 numbers, bring the 5 down. Now we are dividing 175 by 73. 73 goes into 175 2 times. We subtract and end up with 29. From here, the answer depends on if you use remainders or decimals. I am going to assume you use remainders, so the answer would be 12 with a remainder of 29.