At 9: 00 a. m. marsha found a parking meter that still had 5 minute until it expired. she quickly put a quarter, 1 dime, and a nickel into the meter and went to her meeting. if 5¢ buys 15 minute of parking time, at what time will the meter expire

1 quarter + 1 dime + 1 nickel = 25¢ + 10¢ + 5¢ = 40¢

Each 5¢ buys 15 minutes.  How many ' 5¢ ' are in 40¢ ?

40/5 = 8 of them.  So the (quarter+dime+nickel) can buy 8 x 15 minutes = 2 hours.

Starting at 9:00 AM, the meter had 5 minutes left on it, and Marsha bought
another 2 hours.  So now the meter is good until 2 hours and 5 minutes
after 9:00 AM . . . . . 11:05 AM.

The percent increase is 25%

With a continuous thought process.