4. 25/60 * 27 + 36 * 25/60 =

1. Calculate 25/60 * 27: (25/60) * 27 = 0.4167 * 27 = 11.25
2. Calculate 36 * 25/60: 36 * (25/60) = 36 * 0.4167 = 15
3. Add the results: 11.25 + 15 = 26.25