Current Attempt in Progress

Suppose you have a portfolio that has $$250$ in stock A with a beta of $1\mathrm{.}00,$$$1,000$ in stock B with a beta of $1\mathrm{.}30,$ and $$750$ in the riskfree asset. You have another $$500$ to invest. You wish to achieve a beta for your whole portfolio to be the same as the market beta.

What is the beta of the added security? $($Round intermediate calculations and the final answer to $3$ decimal places, e$.$g$.2\mathrm{.}361.)$

Beta