Example exam question:
"Represent the denary value 7.625 as an unsigned binary fixed point number, with 4 bits before and 4 bits after the binary point."
This looks intimidating, but it's really not very complicated once you understand the method.
In order to convert this, we also need to know how how the distance of a digit from the decimal point affects it's value in binary
In base 10 (denary) numbers, each digit of space between the decimal point and a digit increases/decreases it's value by a factor of 10.
1000 100 10 1 . 1/10 1/100 1/1000