Given a math word problem, answer the following question. You might need to apply addition or subtraction mathematical operators on the numbers embedded in the text to answer the question and then only report the final numerical answer.

ryan collected 89 leaves . he lost 24 leaves . after a while 43 more leaves broke . how many leaves are left in his collection ?
22

jennifer has an 87 cm long ribbon . she uses 24 cm of the ribbon to tie a present for her friend and 45 cm of the ribbon to make a bow . how much of the ribbon is left in the end ?
18

there were 10 students riding on the school bus . at the first stop 3 students got off of the bus . how many students are left on the bus ?
7