Integrated Reasoning (IR) | Interest based questions

I want to know the solution for the following question:-

"Loan X has a principal of $10000X and a yearly simple interest rate of 4%. Loan Y has a principle of $10000Y and a yearly simple interest of 8%. Loans X and Y will be consolidated to form Loan Z with a principle of $(10000X + 10000Y) and a yearly SI of r%, where r=(4X+8Y)/(X+Y). what will be the value of X and Y corresponding to a yearly SI of 5% for the consolidated loan."

Thanks in advance!

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