The amount that Marcia will have saved in interest by consolidating the two balances is: b.$133.92.
First step
Calculating for credit card A monthly payment (12% APR) using financial calculator
=pmt(rate,nper,-pv,fv)
Where:
Rate=12%/12=1%
Nper =12 months×4 years=48
PV = $1,389.47
FV=0
Hence:
=pmt(1%,48,-1389.47,0)
=$ 36.59
Second step
Monthly payments 16% APR=$39.38×48
Monthly payments 16% APR =$1890.24
Monthly payments 12% APR=$36.59×48
Monthly payment 12% APR=$1756.32
Third step
Amount saved in interest=$1890.24 -$1756.32
Amount saved in interest=$133.92
Therefore the correct option is B.
Learn more about amount saved in interest here:https://brainly.com/question/27044125
#SPJ1