Ordinary shares of 'Phone Communications' company gave the following returns during

the last four years respectively: $7\mathrm{.}66$; $6\mathrm{.}82$;$9\mathrm{.}42$ and $10\mathrm{.}05\%.$ An investor is considering including

these shares into her portfolio and calculates their risk. What is it$?$

Problem $9$

The 'Real Investments' mutual fund portfolio of ordinary shares includes the following

stocks: 'Paper Inc.$\text{'},$ 'Driving Motors', 'Wooden Co$.\text{'}$ and 'Fuel Oil', that have the given

characteristics:

What is the 'Real Investments' fund return?

Problem $10$

An investor is going to include two assets into her portfolio: ordinary shares of 'White

Paper' and 'Ram Computers' companies. During the last five years these shares gave the

following return respectively: $7\mathrm{.}86$;$8\mathrm{.}42$;$7\mathrm{.}68$;$8\mathrm{.}62$;$8\mathrm{.}22$ and $11\mathrm{.}12$;$12\mathrm{.}44$;$13\mathrm{.}88$;$8\mathrm{.}24$;$10\mathrm{.}12\%.$

What such a portfolio risk would be if the mentioned stocks weights were $2$ to $1?$

When solving this problem apply the formula directly.

Problem $11$

The portfolio includes $4$ stocks: 'Laptop Ltd$.\text{'},$ 'Fast Cars', 'Secure Software' and 'Brown

Paper'. Compute the portfolio risk using the following investment characteristics of its

components.

When solving this problem apply the matrix approach.