2x-2yd=y+xd
2x-y=xd+2yd
2x-y=d(x+2y)
(2x-y)/(x+2y)=d
So the answer is <span><span>d=<span><span>2x−y</span><span>x+2y</span></span></span></span>
It is necessary to include the term one then you will have the plus three
It's 2 7/12
Hope this helped!
John's effective annual rate is about
(1 +.0576/4)^4 -1 ≈ 5.8856%
According to the "rule of 72", John's money will have doubled in
72/5.8856 = 12.23 years
John's balance will be $4500 in 1989.
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Since you're only concerned with the year (not the month), you don't actually need to determine the effective annual rate. The given rate of 5.76% will tell you 72/5.76 = 12.5 years. The actual doubling time is closer to 12.12 years, so using the effective rate gives results that are closer, but "good enough" is good enough in this case.
