The correct numbers to use in solving problems about
spans of time like B.C. and A.D. should be “integers”.
Integers are whole numbers (not a fractional number or not a decimal
number) which can take a value of negative, zero, or positive number. Example
of integers would be -1, 0 and 1.
<span>In calculations, the time period would be on the x-axis. Since
B.C. and A.D. are two different spans of time, therefore in the calculations,
the date of BC should be negative (negative x-axis) while the date of AD should
be positive (positive x-axis). This would place the origin as the common
reference.</span>
