Given data:
The first interest rate is r=7%.
The second interest rate is r'=8%.
The total interest is I=$306.
The principle amount in 8% is p'=p+900.
The given timme is t=1.
The first interest is,
i=(prt)/100
substitute the given values.
i=p(7)(1)/100
=0.07p
The second interest is,
i'=(p'rt')/100
substitute the given values.
i'=(p+900)(8)(1)/100
=0.08(p+900)
=0.008p+72.
The expression for the total interest is,
I=i+i'
Substitute the above-calculated values.
306=0.07p+0.08p+72
234=0.15p
p=1560.
Investment in 8% is,
p'=1560+900
=2460.
Thus, the money invested in 7% account is $1560 and the money invested in 8% account is $2460.