What is the portfolio beta

Question

Problem:

You own a stock portfolio invested 25 percent in Stock Q, 20 percent in Stock R, 5 percent in Stock S, and 50 percent in Stock T. The betas for these four stocks are 1.19, 1.53, 1.24, and 0.78, respectively.

Required:

Question: What is the portfolio beta?

• 1.06
• 1.08
• 1.03
• 1.11
• 1

Note: Could someone please give me a step by step solution?