# math

posted by on .

If computing N(t) = Pa^t where P=642.035376 and a = 2.900129566 (both are stored in calculator), to what extent should the values of N(5), N(7) and N(9) be rounded? and why?

Note:
N(5)= 131,718
N(7)= 1,107,849
N(9)= 9,317,847

algebra - bobpursley, Sunday, November 6, 2011 at 3:18pm
Hmmmm. How many sig digits are in t? ONE? 5,7,9?

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So is the answer is ONE because t (even though it's an exponential and not a factor) only has one sig fig?
I thought it would be the 9 sig figs of P that was the lowest

• math - ,

I am trying to figure out t. If it is a counting number, it is infinitely sigificant, and you are correct on P. If t is a measured number, then it only has one sig digit.

I have no idea the nature of t.

• math - ,

N(t) refers to the number of bacteria after t days.
Does that help? does the exponent t still me answers should be rounded to one sig fig?
N(t) = Pa^t

• math - ,

t in days... is there a number such as t=1.345 days? (yes). So, I would treat t as one sig digit.

n(5)=100,000
n(7)=1,000,000
n(9)=9,000,000