A babysitter charges 25% more than her normal hourly rate on Saturday night. Her normal hourly rate is $12.50.

Which expression represents how much the babysitter charges on Saturday night?

A.
$12.50 x 5/4

B.
$12.50 x 7/4

C.
$12.50 x 1/4

D.
$12.50 x 3/4