OEGiven, Jerry Invested $10,000 at 3% simple Interest and a different amount (say $๐ ) at 10% simple interest. Total interest earned in one year on these two investments together is $900.
Since in the question he is talking about simple interest, so we use the formula of simple interest: ๐.๐ผ. =
๐ร๐ร๐
/100, where
๐ โPrincipal,
๐
โ rate of interest per period
๐ โ number of periods.
Now, using the above formula we get the simple interest earned by the investment $10,000 at the rate of 3% in 1 year as ๐ผ1 = 10,000 ร 1 ร 3/100 where ๐ = 10,000, ๐ = 1 year and ๐
= 3% per annum
Therefore, ๐ผ1= 300
Similarly, the interest earned by the investment of $๐ in another account invested at the rate of 10% in 1 year is given by, ๐ผ2 =๐ ร 1 ร 10/100 where ๐ = ๐, ๐ = 1 year and ๐
= 10% per annum
Therefore, ๐ผ2 = 0.1X
As said in the question, the total interest earned in one year on these two
investments together is $900.
Hence, ๐ผ1 + ๐ผ2 = 900
300 + 0.1๐ = 900
0.1๐ = 600
๐ = $6,000
Ans. $6,000
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