Compare slopes



We have two experimental data sets. Both of them have same independent
variable (X) and dependent variable (Y). For each value of X, we have
triplicate of Y data in each data set. We Plotted these data and fitted
to an equation Y = mX + 1 using MS Excel.

So we have got two linear equations fro these two data sets. Now we
want to compare the slopes of these two straight lines.

Our question: Are there any statistically significant difference
between these two slopes? Can you please let us know how to calculate
it? I am giving the data bellow:

First data set:
X Y
0.1 ---------- 0.66 0.68 0.67
0.2 ---------- 0.63 0.62 0.63
0.5 --------- 0.48 0.47 0.47
1.0 --------- 0.4 0.37 0.35

Second data set
X Y
0.1 ------- 0.38 0.39 0.38
0.2 ------- 0.33 0.34 0.37
0.5 ------0.32 0.31 0.33
1.0 ------ 0.24 0.24 0.25

With regards
Biplab

.