Why Biased Exponent Is Used?

Biasing is done because exponents have to be signed values in order to be able to represent both tiny and huge values, but two's complement, the usual representation for signed values, would make comparison harder.

Why do we use a bias instead of directly reflecting the value of the exponent in the EXP field of a floating point number?

Biasing in floating point number is done because exponents, Have to be signed values. Should be able to represent both smaller and bigger values.

Why do we add 127 to the exponent?

The eight-bit exponent uses excess 127 notation. What this means is that the exponent is represented in the field by a number 127 greater than its value. Why? Because it lets us use an integer comparison to tell if one floating point number is larger than another, so long as both are the same sign.