<h3>$ 950 is in account after 18 years</h3>
<em><u>Solution:</u></em>
Given that,
Principal = $ 500
Rate of interest = 5 %
Number of years = 18
<em><u>The simple interest is given as:</u></em>

Where,
p is the principal
n is the number of years
r is the rate of interest
Therefore,

<em><u>How much money is in his account?</u></em>
Amount = principal + simple interest
Amount = 500 + 450
Amount = 950
Thus $ 950 is in account after 18 years