Amount of money that Caitlin in her account = $ 402
In each week , she withdrew $ 15.
Let number of weeks she had paid money for Swimming lesson = $ 237
Writing the above statement in equation form
⇒ 402 - 15 n = 237
⇒ 402 - 237 = 15 n
⇒ 15 n = 165
Dividing both side by 15, we get
n= 11
→Number of weeks that Caitlin had learnt Swimming = 11 Weeks