Answer
Cook: 54.6 million
Archuleta: 42.9 million
Work Step by Step
Let c = no. of millions of votes won by Cook
Let a = no. of millions of votes won by Archuleta
c = a + 11.7
a + c = 97.5
a + (a + 11.7) = 97.5
2a + 11.7 = 97.5
2a = 85.8
a = 42.9
c = a + 11.7 = (42.9) + 11.7 = 54.6