Calculate the average rate of change of the given function over the given interval. Where appropriate, specify the units of measurement.

f(x) = 1/x;[2, 7]
I used the f(b)-f(a)/b-a and I got -.071 and it said I was wrong could you please help me find my error?

WROK:
y1= 1/x (put this for my y-value in my calculator
then (y1(7)-y1(2))/(7-2) which equals -.071

2 answers

f(2) = 1/2
f(7) = 1/7

avg rate of change = (1/7 - 1/2)/(7-2)
= (-5/14)/5)
= -1/14

don't go with decimals, they are not accurate,
stay with fractions for exact answers.
thank you apparently that is all I had to do=)