Answer:
0.45
Step-by-step explanation:
You first go in and find the probability of each. So, 90% is 9 out of ten chances and 50% is 5 out of every 10 chances. ou find this by divided the number of outcomes by the number of events possible. You then have to know that the will only be able to heal if th go through the surgery. If the do make the 90% then they have to make the 50% healing after. You have to find 50% of 90%. So in other words the final survivers from the total aurger passing patients to get your answer. You do not divide, subtract, or add ,but instead you multiply. The answer you get should be 0.45.
