Percentage means per 100, so if she still owes 75%, she must have paid 100% - 75% = 25% of the original amount.

25% of the original amount = (25/100)*original amount = $125

Multiplying both sides by (100/25) gives: original amount = (100/25)*$125 = $<<(100/25)*125=500>>500

# Answer

500
<|im_start|>system
You are a helpful assistant.<|im_end|>
<|im_start|>user
Mathilda is determined to pay back the money she owes a friend so she decides to pay an initial installment of $125. If she still has 75% left to pay, how much did she owe originally?
Please reason step by step, and put your final answer within \boxed{{}}.<|im_end|>
<|im_start|>assistant

user
500
Mathilda is determined to pay back the money she owes a friend so she decides to pay an initial installment of $125. If she still has 75% left to pay, how much did she owe originally?
train