A clock was set right at 8 a.m. and gains 4 minutes every hour. In the afternoon it reads the time shown. What is the true time?

The clock reads 4:48 p.m., i.e. 8 h 48 min = 528 min after 8 a.m. on its own dial. It runs 64 min for every 60 true min, so the true time passed = $528\times 60÷64=495$ min = 8 h 15 min: 4:15 p.m. (4:12 p.m. subtracts 4 min for each of 8.8 clock hours.)