Here are the returns on two stocks.

Required:

a$-1.$ Calculate the variance and standard deviation of each stock.

a$-2.$ Which stock is riskier if held on its own?

b$.$ Now calculate the returns in each month of a portfolio that invests an equal amount each month in the two stocks.

c$.$ Is the variance more or less than halfway between the variance of the two individual stocks?Here are the returns on two stocks.

Digital Cheese Executive Fruit

January $+19+9$

February $2+1$

March $+4+4$

April $+6+13$

May $3+1$

June $+3+5$

July $12$

August $71$

Required:

a$-1.$ Calculate the variance and standard deviation of each stock.

a$-2.$ Which stock is riskier if held on its own?

b$.$ Now calculate the returns in each month of a portfolio that invests an equal amount each month in the two stocks.

c$.$ Is the variance more or less than halfway between the variance of the two individual stocks?