Suppose a risk-free asset has a 5 percent return and a second asset has an expected return of 13 percent with a standard deviation of 23 percent. Calculate the expected return and standard deviation of a portfolio consisting of 10 percent of the risk-free asset and 90 percent of the second asset.
Jones, Charles P.; Jensen, Gerald R.. Investments: Analysis and Management, 13th Edition (Page 191). Wiley. Kindle Edition.