Let
x--------> the estimated population of Chicago in 2010
y--------> the estimated population of Illinois in 2010
we know that
[tex]x=2.7*10^{6}\ people[/tex] ------> equation 1
[tex]y=4.76x[/tex] ------> equation 2
Substitute equation 1 in equation 2
[tex]y=4.76*2.7*10^{6}[/tex]
[tex]y=1.2852*10^{7}\ people[/tex]
[tex]y=12,852,000\ people[/tex]
therefore
the answer is
the approximate population of the state of Illinois in 2010 is
[tex]y=12,852,000\ people[/tex]
