Answer: beta of your portfolio = 1.80

Working notes for the above answer is as under

First determine the total value of the portfolio and the weights of each stock in the portfolio: Total value

= $32,000 + $43,500 + $21,700

= $97,200

Olympic Steel weight

= $32,000 / $97,200

= 32.92%

Rent-a-C0 weight

= $43,500 / $97,200

= 44.75%

Lincoln Educational weight

= $21,700 / $97,200

= 22.32%

Now compute the portfolio beta:

=(0.3292×3.42) + (0.4475×1.87) + (0.2232×-0.73)

= 1.7998

=1.80