To calculate the new balance on Guadalupe's credit card, we need to consider the previous balance, any new charges, and the amount of the principal that has been paid off.
Let's break down each month using the transaction details provided in the table:
### Month 1:
- Previous balance: \[tex]$0.00
- New charges: \$[/tex]900.00
- Payment received: \[tex]$0.00
- Finance charges: \$[/tex]0.00
- Principal paid: \[tex]$0.00
- New balance: \$[/tex]900.00
### Month 2:
- Previous balance: \[tex]$900.00
- New charges: \$[/tex]0.00
- Payment received: \[tex]$18.00
- Finance charges: \$[/tex]17.25
- Principal paid: \[tex]$0.75
- New balance: \$[/tex]899.25
### Month 3:
- Previous balance: \[tex]$899.25
- New charges: \$[/tex]0.00
- Payment received: \[tex]$17.99
- Finance charges: \$[/tex]17.24
- Principal paid: \[tex]$0.75
- New balance: \$[/tex]898.50
### Month 4:
- Previous balance: \[tex]$898.50
- New charges: \$[/tex]0.00
- Payment received: \[tex]$17.97
- Finance charges: \$[/tex]17.22
- Principal paid: \[tex]$0.75
- New balance: \$[/tex]897.75
### Month 5:
- Previous balance: \[tex]$897.75
- New charges: \$[/tex]0.00
- Payment received: \[tex]$17.96
- Finance charges: \$[/tex]17.21
- Principal paid: \[tex]$0.75
- New balance: \$[/tex]897.00
### Month 6:
- Previous balance: \[tex]$897.00
- New charges: \$[/tex]0.00
- Payment received: \[tex]$17.94
- Finance charges: \$[/tex]17.19
- Principal paid: \[tex]$0.75
- New balance: \$[/tex]896.26
### Month 7:
- Previous balance: \[tex]$896.26
- New charges: \$[/tex]0.00
- Payment received: \[tex]$17.93
- Finance charges: \$[/tex]17.18
- Principal paid: \[tex]$0.75
- New balance: \$[/tex]895.51
We observe that the new balance is calculated by adding any new charges to the previous balance and then subtracting the principal paid. Therefore, the correct formula for calculating the new balance is:
[tex]\[ \text{New balance} = \text{Previous balance} + \text{New charges} - \text{Principal paid} \][/tex]
Thus, the correct answer is:
C. Previous balance + new charges - principal paid
