An infectious strain of bacteria increases in number at a relative growth rate of 200% per hour. When a certain critical number of bacteria are present in the bloodstream, a person becomes ill. If a single bacterium infects a person, the critical level is reached in 24 hours. How long will it take the critical level to be reached if the same person is infected with 10 bacteria?

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Answer: It will take 2.4 hours or 2 hours 24 minutes for the critical level to be reached if a person gets infected with 10 bacteria

Step-by-step explanation:

*From the question, bacteria increases in number at a growth rate of 200 percent per hour

*If one bacterium infects Mrs Williams for example, in 24 hours Mrs Williams will fall ill.

*Now this means that one bacterium growing at 200% per hour in Mrs Williams' body must have grown to 4800% in 24 hours for her to fall ill

That is: 200%---------1hour

?% --------- 24hours

24/1 ×200 =4800%

Now, if 10 bacteria infects Mrs Williams, how long will it take for her to fall ill? (In another way, when will the critical level of 4800% bacteria be reached?)

1 bacterium grows at -----200% in 1 hour

10 bacteria will grow at----- ?% in 1 hour

That is, 10/1 × 200 = 2000%

This means that 10 bacteria will grow at 2000 percent per hour.

So, if 10 bacteria grows at 200% per hour and consequently infects Mrs Williams, they will grow to 4800% in 2.4 hours and thereby causing the woman to fall sick in just 2.4 hours

That is, 10 bacteria grows at 2000%------1hour

They'll grow to 4800% in -----? hours

= 4800/2000 ×1= 2.4 hours.

Since 60 minutes make 1 hour, 0.4 hours will be: 0.4 ×60 = 24 minutes

Therefore the time required for 10 bacteria infecting a person to reach a critical level before he/she becomes ill is 2hours 24 minutes

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