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Solution: Problem 1

a) The transition matrix A is $ \left[ \begin{array}{rr}
0.92&0.04\\
0.08&0.96\\
\end{array}\right]$

b) The number of math students after one year is the first component of the vector $ x_1= A x_0$.

$ x_1= A x_0 =
\left[ \begin{array}{rr}
0.92&0.04\\
0.08&0.96\\
\end{array}\ri...
...\\
\end{array}\right]
\left[ \begin{array}{r}
198\\
352\\
\end{array}\right]$

Hence the number of the mathematics major is 198.

c) The number of biology students after three years is 355. It is determined by $X_3=A^3 X_0$

Since $ A^3 = \left[ \begin{array}{rr}
0.7876 & 0.1062\\
0.2124 & 0.8938\\
\end{array}\right]
$

$ x_3 = A^3 x_0 =
\left[ \begin{array}{rr}
0.7876 & 0.1062\\
0.2124 & 0.8938\...
...ay}\right]
=
\left[ \begin{array}{r}
194.6912\\
355.3088\\
\end{array}\right]$

Hence there will be 355 Biology majors at senior year.


Ali A. Daddel 2000-09-16