Stanley and Sara purchase real estate for $600,000 and list ownership as follows: " Stanley and Sara, joint tenants with the right of survivorship." Stanley contributed $240,000 of the purchase price and Sara contributed the remaining $360,000. Stanley dies first, when the real estate is valued at $860,000.

I understand b: as $ 430,000.00 because husband and wife split this 50/50, however I thought a would be 0 since the right of survivorship exists and it shows incorrect. Can someone help me?