Tim has a savings account with the bank. The bank pays him 2% per year. He has $4,700 and wonders
when it will reach $4,900. When will his savings reach $4,900? If necessary, round your answer to the
nearest whole number.

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If we set the vertex at (0,0) then the curve goes through (30,30) 

y = 1/30 x^2 
x^2 = 30y 

Since the parabola x^2 = 4py has its focus at y=p, 4p=30 and the mic should be 15/2 inches up from the vertex.