# College Algebra

posted by Marlon

I am having a difficult time with this question. Any help whatsoever will be really helpful as I have been pulling an all nighter for my test at 4pm.

Suppose that y=[2-log(100-x)]/0.29 can be used to calculate the number of years y for x percent of a population of 928 web-footed sparrows to die. Approximate the percentage (to the nearest whole percent) of web-footed sparrows that died after 5 years.

The answer is supposed to be 96% but I am just not getting it. I have a feeling its not hard but I'm missing something crucial.

Thanks for all the help!

1. bobpursley

.29*5=2-log(100-x)
log(100-x)=.55
100-x=3.55
x=96.4

2. Marlon

=/
I still do not understand. This is my setup.

5=[2-log(100-x)]/.29
1.45 = 2-log(100-x)
-.55 = -log(100-x)
.55= log(100-x)
Now I am frozen there... If i take the log of both sides I do have 100-x on the right but obtain -.2596 for the left. The problem would equal 100.2596 and not 96.4.

In your setup, I am confused as to where the 100-x=3.55 came from.

Thank you so much, you don't understand how helpful you guys are for taking the time to help us.

3. bobpursley

1.45=2-log(100-x)
-.55=-log(100-x)
.55=log(100-x)
take the antilog of each side
3.458133892=100-x

You are taking the LOG of both sides. You want the antilog.

4. Marlon

Thank you so much!!! I got it!

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