When a tree was first planted, it was 4 feet tall and its height increased at a constant rate for the next 6 years. At the end of 6 years, the tree was 1/5 taller than it was at the end of the 4th year. By how many feet did the tree increase each year?
What's the best way to attack this?
Thanks!
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muzali
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Set up an arithmatic progression:
a=4 (4ft tall to begin with)
d = rate of growth every year
End of 1st year, height = a+d
End of 2nd year, height = a+2d
End of 4th year, height = a+4d
End of 6th year, height = a+6d
it is given that a+6d = (6/5)(a+4d)
we know a, solve for d to get the answer.
a=4 (4ft tall to begin with)
d = rate of growth every year
End of 1st year, height = a+d
End of 2nd year, height = a+2d
End of 4th year, height = a+4d
End of 6th year, height = a+6d
it is given that a+6d = (6/5)(a+4d)
we know a, solve for d to get the answer.
