Question 962644
{{{ A = P*( 1 + r/n )^( n*t ) }}}
{{{ n = 12 }}}
{{{ t = 4 }}}
{{{ P = 1900 }}}
{{{ A = 2250 }}}
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{{{ 2250 = 1900*( 1 + r/12 )^( 12*4 ) }}}
{{{ 1.18421 = ( 1 + r/12 )^48 }}}
Take the log of both sides
{{{ .073429 = 48*log( 1 + r/12 ) }}}
{{{ .0015298 = log( 1 + r/12 ) }}}
{{{ 10^.0015298 = 1 + r/12 }}}
{{{ 1.0035287 = 1 + r/12 }}}
{{{ r/12 = .0035287 }}}
{{{ r = .042344 }}}
The rate is 4.23%
check:
{{{ 1.18421 = ( 1 + r/12 )^48 }}}
{{{ 1.18421 = ( 1 + .042344/12 )^48 }}}
{{{ 1.18421 = ( 1 + .003529 )^48 }}}
{{{ 1.18421 = 1.18421 }}}
OK