0.5=½,
0.5×96.4=96.4/2=48.2.
Another way to solve is to calculate 5×964=4820.
Now, count how many digits follow the decimal point for each number.
So for 0.5 there is one digit, and there is also one digit after the decimal point in 96.4. 1+1=2 so we need a decimal point two places from the right in 4820, which gives us 48.20. We can omit the final zero, because it doesn’t alter the result: 48.2, which is the answer we got before.