It takes Jack 2 more hours than Tom - PS (>700)

[GMAT_ClubMBA]

It takes Jack 2 more hours than Tom to type 20 pages. If working together, Jack and Tom can type 25 pages in 3 hours, how long will it take Jack to type 40 pages?

A. 5
B. 6
C. 8
D. 10
E. 12

respuesta: show

E