This is a geometric sequence. Recall that geomectic sequences take the form: S = Sum (i = 0 to n) a*r^i. In this case, a = 1, r = 2, and n = 30. So you have S = Sum (i = 0 to 30) 2^i. Remember to change the Sum to the capitol sigma.Can't seem to nail down the equation for this problem...?
Lets work it out.
d1 - 0.01
d2 - 0.02
d3 - 0.04
d4 - 0.08
d5 - 0.16
d6 - 0.32
d7 - 0.64
d8 - 1.28
d9 - 2.56
d10 - 5.12
d11 - 10.24
d12 - 20.48
d13 - 40.96
...
and so on until my hand gets sore.
Using a calculator it turns out he'd get $10,737,418.23 by that method.
And only $1,000,000 by the other method.
As for the equation, there's a quick way to work out the first one. Consider working for 5 days:
2^0 + 2^1 + 2^2 + 2^3 + 2^4 =
1 + 2 + 4 + 8 + 16 = 31 cent
But if you do: 2^5 - 1 (32cent - 1cent) you arrive at the same answer a lot faster.
So instead of doing:
2^0 + 2^1 + 2^2 + 2^3 ... 2^27 + 2^28 + 2^29 = answer
You can do: 2^30 - 1 = $10,737,418.23
Hope that helps.
u see the pattern but there is an equation
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