There’s a zombie outbreak in a city of 20 million people and the army has been o

Question

There’s a zombie outbreak in a city of 20 million people and the army has been ordered to deal with it. Since you are the general, that means you have to decide what to do. One option is that you could send in all of your troops, but then you would have none to spare if there’s another outbreak somewhere else. Instead, you decide to send in a smaller force of just 2,000 soldiers with orders to recruit members of the public to help them fight the zombies. This solution leaves you with plenty of soldiers in case there are any other outbreaks, but no one else thinks it will work. To prove them wrong, you set out to do the calculations. You know that each soldier can hunt down and kill 15 zombies a day. In the evening, each soldier can also recruit one new soldier from the people in the city who will join the army the following day and fight the zombies. However, each night, the zombies will fight back and each one will infect five normal people who then become zombies. You know that there are currently 60,000 zombies in the city. Have you made the right decision?
1. Calculate the number of zombies and soldiers at the start of each day from Day 1 to Day 10. If the number of zombies at the start of the day becomes 0, then the threat has been eliminated. Make a list (you can use MS Word, Excel, pencil and paper, etc… to do the calculations). Write in the lab report your results from Days 1–10.
2. Modify your input for a different number of soldiers. Try 2,500 soldiers to begin with. How does this change the results? Write a summary of your findings.

Explanation / Answer

Answer:

1) State of soldiers and jombies at the start of each day is shown in the following table:

It is clear from the calculation that 2000 soldiers in start will not be enough to wipe out the jombies in 10 days. Hence, this won't prove to be a good decision.

2) See the table with 2500 soldiers below:

It is clear this also won't be sufficient to wipe out jombies till the end of 10th day although remaining jombies at the end of 10th day will be much less as that in comparison to 2000 soldiers

So we will definitely need to try with more soldiers. We will increase number soldiers by 500 for each new calculation.

a) With 3000 soldiers:

So, now we can see that with 3000 soldiers, jombies can be eliminated in 2 days. There will be no jombie left at the end of 2nd day.

No. of Days No. of soldiers at start of day No. of Jombies at start of day No. of Jombies killed in a day No. of remaining Jombies at end of day No. of New Jombies at end of day No. of new soldiers at end of day 1 2000 60000 30000 30000 150000 2000 2 4000 180000 60000 120000 600000 4000 3 8000 720000 120000 600000 3000000 8000 4 16000 3600000 240000 3360000 16800000 16000 5 32000 20160000 480000 19680000 98400000 32000 6 64000 118080000 960000 117120000 585600000 64000 7 128000 702720000 1920000 700800000 3504000000 128000 8 256000 4204800000 3840000 4200960000 21004800000 256000 9 512000 25205760000 7680000 25198080000 1.2599E+11 512000 10 1024000 1.51188E+11 15360000 1.51173E+11 7.55866E+11 1024000

Related Questions

Navigate

• Browse (All)
• Browse T
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.