Philip P. answered • 10/29/21
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a) t = 2030 - 2010 = 20. P(2030) = 6.9(1.011)20. Use you calculator to get the answer.
b) P(t) = 6.9 (1.011)t. In 2010, t = 0 and P(2010) = 6.9 billion. Double that is 13.8 billion. So:
P(t) = 6.9 (1.011)t
13.8 = 6.9 (1.011)t
2 = 1.011t
log(2) = log(1.011t)
log(2) = t log(1.011) [ log property: log(ab) = b log(a) ]
log(2) / log (1.011) = t
Use your calculator to get t. You can use any base log. The year is 2010 + t. Round down to the nearest year.
Jsmn V.
i don't get the letter b
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10/30/21
Philip P.
In (b), you have to solve for the year (t + 2010) when the population doubles. Initial population is 6.9 billion, twice that is 13.8 billion. So we set P(t) = 13.8 and then solve for t. t is up in the exponent., so you have to use a log to get it down out of the exponent. Use your calculator to solve log(2) / log(1.011) to get t. You can use log base 10.
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10/30/21
Jsmn V.
how can you calculate the letter b po?10/30/21