Answer:
After 33 weeks.
Step-by-step explanation:
Let w be number of weeks.
We have been given that Gina opened a bank account with $40. She plans to add $20 per week to the account and not make any withdrawals. So the balance after w weeks will be 20w+40.
To figure out number of weeks Gina will have exactly $700 in her account, we will equate the balance after w weeks to 700.
[tex]20w+40=700[/tex]
Let us subtract 40 from both sides of equation.
[tex]20w+40-40=700-40[/tex]
[tex]20w=660[/tex]
Upon Dividing both sides of our equation by 20 we will get,
[tex]\frac{20w}{20}=\frac{660}{20}[/tex]
[tex]w=\frac{660}{20}[/tex]
[tex]w=33[/tex]
Therefore, after 33 weeks Gina will have exactly $700 in her account, excluding interest.
