Medical Ray
Riddle: You are a famously smart doctor who has been assigned to cure a patient who has a virus in his body. Luckily, you have a ray gun which can shoot a concentrated beam of energy to kill the virus. Unfortunately, the beam is so strong that it will kill any vital tissues that touch the beam as well. You can, however turn the gun down to 1/10 of it's power, and it won't harm the tissues. It will not, however, kill the virus. How do you kill the virus without harming the tissues?
Answer: Surround the patient with 10 ray guns set to 1/10 the power. This way, the virus will be hit with a concentrated area of energy while the tissues remain intact.
Source: https://www.riddles.com/index.php/2642
