The number of months that she can withdraw $40 is 6 months.
The equation that can be used to determine the number of times she can withdraw $40 and still have at least $150 is:
$150 = $390 - $40x
Where: x is the number of withdrawals
In order to determine the value of x, take the following steps
Combine similar terms: $390 - $150 = $40x
Add similar terms: $240 = $40x
Divide both sides of the equation by $40
x = 6
To learn more about division, please check: https://brainly.com/question/194007