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# Exponential model word problem: bacteria growth

CCSS.Math:

## Video transcript

the bacteria in a petri dish culture ourself duplicating at a rapid pace the relationship between the elapsed time T in minutes and the number of bacteria B of T in the petri dish is modeled by the following function we see it's an exponential model here how many bacteria will make up the culture after 120 minutes so really they just want to say well what is B of 120 going to be and so it's going to be 10 times 2 to the 120 divided by 12 power so this is going to be equal to 10 times 2 to the 120 divided by 12 is 10 power so this is going to be equal to 10 times 2 to the 10th power is 1,024 if you want to verify that you could say well 2 to the fifth is equal to 32 and so 2 to the 10th is going to be to the 5th times to the 5th and 32 times 32 is let's see 64 0 6 so let's see we're going to have 6 so 3 times 32 is 96 so you have a 4-12 1024 so this is going to be 1024 10 times that is going to be equal to 1 0 2 4 0 so ten thousand two hundred ten thousand two hundred and forty bacteria and we're done