Question 1101045
{{{ I[1] = P[1]*r[1]*t }}}
and
{{{ I[2] = P[2]*r[2]*t }}}
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{{{ I[2] = 618 - I[1] }}}
{{{ P[2] = 7200 - P[1] }}}
{{{ r[1] = .1 }}}
{{{ r[2] = .08 }}}
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{{{ I[1] = P[1]*.1*1 }}}
{{{ 618 - I[1] = ( 7200 - P[1] )*.08*1 }}}
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{{{ I[1] = .1P[1] }}}
and
{{{ 618 - I[1] = 576 - .08P[1] }}}
{{{ I[1] = .08P[1] + 42 }}}
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{{{ .1P[1] = .08P[1] + 42 }}}
{{{ .02P[1] = 42 }}}
{{{ P[1] = 2100 }}}
and
{{{ 7200 - P[1] = 7200 - 2100 }}}
{{{ 7200 - P[1] = 5100 }}}
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$2,100 was invested @ 10%
$5,100 was invested @ 8%
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check:
{{{ I[1] = .1P[1] }}}
{{{ I[1] = .1*2100 }}}
{{{ I[1] = 210 }}}
and
{{{ I[2] = .08P[2] }}}
{{{ I[2] = .08*5100 }}}
{{{ I[2] = 408 }}}
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{{{ I[1] + I[2] = 210 + 408 }}}
{{{ I[1] + I[2] = 618 }}}
OK