SOLUTION: i need help with this problem: This is the model showing the percentage of Americans with heart disease who are "x" years old:
90/1+271e^-0.122x
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Question 377680: i need help with this problem: This is the model showing the percentage of Americans with heart disease who are "x" years old:
90/1+271e^-0.122x
At what age will the percentage of Americans with heart disease be 70%?
I'm thinking it works like this:
0.7 = 90/1+271e^-0.122x
ln 0.7= ln (90/1+271e^-0.122x)
NOW I AM STUCK!!!!! WHAT NOW???!!!! THX!!
Found 2 solutions by Fombitz, stanbon:
Answer by Fombitz(32388) (Show Source): You can put this solution on YOUR website!
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Now take the natural log of both sides.
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Answer by stanbon(75887) (Show Source): You can put this solution on YOUR website!
This is the model showing the percentage of Americans with heart disease who are "x" years old:
90/1+271e^-0.122x
At what age will the percentage of Americans with heart disease be 70%?
I'm thinking it works like this:
0.7 = 90/1+271e^-0.122x
----------------------------
Try this:
70 = 90/[1+271e^-0.122x]
----
1 + 271e^-0.122x = 90/70 = 1.2857
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271e^-0.122x = 0.2857
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e^-0.122x = 0.004744
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Take the ln to get:
-0.122x = -5.3508
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x = 43.86 yrs old
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Cheers,
Stan H.
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