Answer: Our required equation would be

Step-by-step explanation:
Since we have given that
Amount the first runner has in savings = $112
Amount the first runner received a gift from a friend = $45
Amount the first runner saved each month = $25
Let the number of months be 'm'.
So, Total amount in the first runner account is given by

Similarly,
Amount the second runner has in savings = $50
Amount the second runner saved each month = $60
so, the total amount in the second runner account is given by

According to question, Both the accounts have same amount of money.
So, it becomes,

Hence, our required equation would be
