A bacteria culture begins with 13 bacteria that triple in amount at the end of every hour. How many bacteria exist in the culture at the end of the 10th hour?
a. 13,312
b. 26,624
c. 767,637
d. 2,302,911

Question

A bacteria culture begins with 13 bacteria that triple in amount at the end of every hour. How many bacteria exist in the culture at the end of the 10th hour? 
a. 13,312
b. 26,624
c. 767,637
d. 2,302,911

anonymous · Answer

c

anonymous · Answer

yea but how, i tried and got 255879

anonymous · Answer

#of bacteria = 13(3)^n

where 'n' is the number of years. 

so 13(3)^10 = 767637

anonymous · Answer

no i thought it was 13(3)^(10-1)

anonymous · Answer

Why would you do that?

anonymous · Answer

being that the formula is an = a1(r)^(n-1)

anonymous · Answer

That's for geometric sequence. This is an exponential equation, not a geometric sequence.

anonymous · Answer

oh so how do u no what is different

anonymous · Answer

General formula-->  c= a(b)^n

It's like the compound interest formula. a = initial amount/money. b = rate of increase/how many times it get's multiplied. n = number of times it happens/number of years.

anonymous · Answer

oh okay, i hope ur right... thank u!

anonymous · Answer

Anytime.

anonymous · Answer

Was correct, ty!