Skip to content

FRM Part I · FRM Exam Part I · Modern Portfolio Theory (MPT) and the Capital Asset Pricing Model (CAPM)

Asset A has a volatility of 20% and Asset B has a volatility of 30%. A portfolio holds 60% in A and 40% in B, and the correlation between the two assets is 0.5. What is the portfolio volatility?

Portfolio variance is 0.0432, found by adding the two squared-weight variance terms and twice the weighted covariance term, each equal to 0.0144. The square root gives 20.78%. This is below the 24% weighted average because the correlation of 0.5 is less than 1, so diversification reduces risk.

  1. A20.78%Correct
  2. B24.00%
  3. C16.97%
  4. D18.97%

Explanation

Variance = 0.6^2(0.04) + 0.4^2(0.09) + 2(0.6)(0.4)(0.5)(0.2)(0.3) = 0.0144 + 0.0144 + 0.0144 = 0.0432, so volatility = 20.78%. The 24% option is the weighted average of volatilities, which holds only when correlation is 1. The 18.97% option leaves out the factor of 2 on the covariance term.

Did you get it right without looking?

One question tells you little. A timed set on Modern Portfolio Theory (MPT) and the Capital Asset Pricing Model (CAPM) shows your real accuracy, how long you take and where you lose marks.

More Modern Portfolio Theory (MPT) and the Capital Asset Pricing Model (CAPM) questions