Question 1157067
<br>
Sara: 400 + 445 + 490 + ... + 1120 + 1165 = 18((400+1165)/2) = 14085<br>
John: 4.35+8.70+17.40+...+...<br>
The amount John saves in the 17th month is<br>
{{{4.35*2^17 = 570163.20}}}<br>
Doubling the amount each month makes the total grow so fast that John could save a nickel ($0.05) the first month and still end up with more than Sara at the end of 18 months.<br>