The answer is 24.5 because

so you add 5.5 from 19 to get the answer
You can solve this analytically to get
.. 55000*(1 +x/100)^10 = 108193
.. (1 +x/100)^10 = 108193/55000
.. 1 +x/100 = (108193/55000)^(1/10)
.. x = 100*((108193/55000)^(1/10) -1) ≈ 7.00
but I find it just as fast to have a graphing calculator do it.
The city's population is increasing 7% per year.
Y = 3/5x + b
3 = 3/5(-1) + b
3 = -3/5 + b, b = 3 3/5
Y = 3/5x + 3 3/5
<span>Income earned over one year is principal * int rate so we have
0.12*A + 0.13*B +0.14*C = 400
and A + B + C = 3000
and A+B = C</span>