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?
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
#### 500