The amount invested by Mr.Smith in 5% is $240 .
<u>Step-by-step explanation:</u>
We have , Mr. Smith invests a certain amount of money at 8% and twice as much at 5%. If his annual income from the two investments is $720 . Let us suppose that Mr.Smith invest $x so :
Amount of money invested in 5% is . And, amount of money invested in 8% is twice that of 5% i.e. .
Now, total investment is $720 so,
+( ) = $720
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The amount invested by Mr.Smith in 5% is i.e.. ∴ The amount invested by Mr.Smith in 5% is $240 .