If samantha can pay off her loan in 36 months at a 10% interest rate rather than in 48 months at a 12% interest rate, how much money will she save in interest charges on her $6,000 loan?

Hi there
The simple interest formula is
I=prt
I interest changes
P amount of the loan 6000
R interest rate
T time( number of months/12 months)

The interest in 36 months at a 10%
I=6,000×0.1×(36÷12)=1,800
The interest in 48 months at a 12%
6,000×0.12×(48÷12)=2,880
she will save
2,880−1,800=1,080

Good luck!