Yen read 4 books in 2 h 24 min. She took the same amount of time to read each of the first 3 books. She took 32 min longer to read the fourth book than each of the first 3 books. She finished reading all the books at 15 14. What time did she start reading the fourth book?
Duration that Yen took to read the first book = 1 u
Duration that Yen took to read the second book = 1 u
Duration that Yen took to read the third book = 1 u
Duration that Yen took to read the fourth book = 1 u + 32 min

Total duration that Yen took to read the four books 
= 1 u + 1 u + 1 u + 1 u + 32 min
= 4 u + 32 min

4 u + 32 min = 2 h 24 min
4 u = 144 min - 32 min
4 u = 112 min  

1 u = 112 min ÷ 4 = 28 min

Duration that Yen took to read the fourth book
= 28 min + 32 min
= 60 min
= 1 h

1 h before 15 14: 14 14

Time that Yen started to read the fourth book = 14 14

Answer(s): 14 14