Final answer:
The range of decimal values for a signed byte is -128 to 127 in the case of an 8-bit signed byte.
Step-by-step explanation:
The range of decimal values for a signed byte can be calculated using the formula -2^(n-1) to 2^(n-1) - 1, where 'n' is the number of bits used to represent the signed byte. In the case of an 8-bit signed byte, the range is -128 to 127.