Answer:
2 mosquitoes would be killed on the sixth day.
Explanation:
To model this situation of exponential decay, we use y=a(b)^x. Y would represent the mosquitoes killed after so many days of the spraying, a would be the initial amount of mosquitoes, b would be how much it decreases each time, and x is days after the spraying. To get the original amount of mosquitoes, we multiply 2400 by 4 and get 9600. I did this because I noticed that each day, you can divide the previous number by 4. Then, our b would be 1/4 because 600 is one fourth of 2400, 150 is one fourth of 600, and so on. Then, I put this into my calculator: 9600(1/4)^6. This gave me 2.34375 but you would round to 2 mosquitoes. Hope this helps :)