Let
Cp= Charlie's page
Gp= George's page
Bp= Bill's page
To get Charlie's page:
2 (Cp+50)- Cp=210
2 Cp + 100-Cp=210
Cp= 210-100
Cp= 110
to get Bill's page:
Bp=Cp+50
= 110+50
Bp= 160
to get George's page
Gp=2(Bp)
= 2(160)
Gp= 320
therefore:
Cp= Charlie's page has 110
Gp= George's page has 320
Bp= Bill's page has 160