Question 1095261
Assuming simple interest:
{{{ I[1] = P*r[1]*t }}}
{{{ r[1] = .09 }}}
{{{ t = 1 }}}
{{{ I[1] = .09P }}}
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{{{ I[2] = 2P*r[2]*t }}}
{{{ r[2] = .12 }}}
{{{ t = 1 }}}
{{{ I[2] = .24P }}}
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given:
{{{ i[1] + I[2] = 1320 }}}
{{{ .09P + .24P = 1320 }}}
{{{ .33P = 1320 }}}
{{{ P = 4000 }}}
and
{{{ 2P = 8000 }}}
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She invests $4,000 @ 9%
She invests $8,000 @ 12%
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check:
{{{ I[1] = .09P }}}
{{{ I[1] = .09*4000 }}}
{{{ I[1] = 360 }}}
and
{{{ I[2] = .24P }}}
{{{ I[2] = .24*4000 }}}
{{{ I[2] = 960 }}}
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{{{ I[1] + I[2] = 1320 }}}
{{{ 360 + 960 = 1320 }}}
{{{ 1320 = 1320 }}}
OK