Respuesta :
Answer:
Amount invested at 4% is $16,000
Amount invested at 9% is $6,000
Step-by-step explanation:
Let one vestment be x
if total investment is $22,000 then
other investment will $22,000 - x
simple interest earned in any year is given by
SI = p*r*t/100
where SI is the interest earned
t is the time period of investment
r is the rate of annual interest
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interest on one account 4%
p = x
t = 1 year
SI = x*4*1/100 = 4x/100
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interest on one account 9%
p = 22,000 - x
t = 1 year
SI = (22,000 - x)*9*1/100 = (198000 - 9x)/100
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it is given that total interest earned was $1180
thus sum of SI calculated for the 9% and 4% investment will be equal to 1180
4x/100 + (198000 - 9x)/100 = 1180
=> (4x+198000 - 9x)/100 = 1180
=> 198000 - 5x = 1180*100
=> -5x = 118,000 - 198000
=> -5x = -80,000
=> x = -80,000/-5 = 16,000
Thus,
Amount invested at 4% is $16,000
Amount invested at 9% is $(22,000 - 16,000) = $6,000
