Four staff members at a certain company worked on a project. The amounts of time that the four staff members worked on the project were in the ratio 2 to 3 to 5 to 6. If one of the four staff members worked on the project for 30 hours, which of the following CANNOT be the total number of hours that the four staff members worked on the project?

A. 80

B. 96

C. 160

D. 192

E. 240

我算出来范围是90-240

所以选了a答案是D

2份，3份，5份和6份，一共16份

假设30是2份，1份是15， 总共15*16=240

假设30是3份，1份是10， 总共10*16=160

假设30是5份，1份是6，总共6*16=96

假设30是6份，1份是5，总共5*16=80

能理解了吗？