Question 880717
The formula is:
{{{ Q(t) = 5.3( 1 + .02 )^t }}}
where {{{ Q(t) }}} is in billions
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The population has doubled when
{{{ Q(t) = 10.6 }}} billion
I can then say:
{{{ 10.6 = 5.3( 1 + .02 )^t }}}
{{{ 2 = 1.02^t }}}
{{{ log(2) = t*log(1.02) }}}
{{{ t = log(2) / log(1.02) }}}
{{{ t = .30103 / .0086 }}}
{{{ t = 35.003 }}}
The population will double in 35 years
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check:
{{{ Q(35) = 5.3( 1 + .02 )^35 }}}
{{{ Q(35) = 5.3*1.02^35 }}}
{{{ Q(35) = 5.3*2 }}}
{{{ Q(35) = 10.6 }}}
OK