fp1 more linear laws

This is the question

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t = 1 2 3 4 5
m = 24 28.9 34.5 41.5 49.8

It is believed that a formula such as m = ab^t connects m and t.

Find the values of a and b.

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I've done
ln m = ln a + tlnb

then I've used the scatter graph and regression calculator as follows:

entered x values with the t values
entered y values with ln m values

then I've looked at rg ax+b and got a =0.182 and b = 2.9


The answer in the book is a=20, b= 1.2.


I would appreciate some pointers.

Thanks

I have just put the values into this regression calculator and I get what the book gets

http://www.easycalculation.com/statistics/regression.php

Oh - I see what you have done

you have a and b the wrong way round and you have forgotten to raise e to the power

Thanks - what with a and b in the question and and b on the calculator I got in a real muddle and then didn't do the final step.

Thanks - what with a and b in the question and and b on the calculator I got in a real muddle and then didn't do the final step.

So change the letters in the question to something different from a and b, rather than using the same letters to stand for two different quantities (a useful hint for all Maths).