Final answer:
To calculate the initial plt count 6 days before surgery, subtract the current count from the original count to determine the decrease, then add that decrease back to the current count. The initial count would be 140,000 platelets.
Step-by-step explanation:
The question is asking to find the initial platelet count (plt count) 6 days before surgery given that the count is 50,000 now and was originally 140,000. This is a simple subtraction problem. If the plt count has decreased from 140,000 to 50,000, then the difference between these two numbers will give us the amount it has decreased by. The count has decreased by 140,000 - 50,000, which equals 90,000. Therefore, the initial plt count 6 days before surgery would have been 50,000 + 90,000, which is 140,000 platelets.