Question 279263
AT 8AM 7 PEOPLE HAVE HEARD A RUMOR. AT 11AM 75 PEOPLE HAVE HEARD THE SAME RUMOR. LET F(T) REPRESENT THE NUMBER OF PEOPLE WHO HAVE HEARD THE RUMOR T HOURS AFTER 6AM AND ASSUME THAT THE NUMBER OF PEOPLE IS GROWING EXPONENTIALLY. FIND AN EQUATION FOR F(T), AT WHAT RATE IS THE RUMOR SPREADING, DETERMINE THE TIME IT TAKES FOR 1500 PEOPLE TO HEAR THE RUMOR.
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i am assuming that the rumor started at 6am and by 8am only 7 people had heard the rumor.
0::::::1 person
2::::::7 people
5::::::75
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If the relation is exponential, the least-squares regression
equation is 
F(T) = 1.09(2.3578)^x
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The the time (x) for 1500 people results from 
solving 1.09(2.3578)^x = 1500
2.3578^x = 1376.15
x = log(1376.15)/log(2.3578)
x = 8.4257 hours
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Time would be 6AM + 8.4257 hrs 
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cheers,
Stan H.