John sold his 2nd-hand car to Marie for P200,000. They agreed that John will pay half of the purchase price, or P100,000, upon delivery of the said car to Marie, and the balance of P100,000 shall be paid in five (5) equal monthly installments of P20,000 each. The car was delivered to Marie, and she paid P100,000 to John. Shortly thereafter, the car was stolen from Maries garage without her fault and was never recovered. Is Marie still legally bound to pay John the unpaid balance of P100,000? Explain your answer.