Answer:
For the 9% she invested $2,300
For the 10% she invested $2,500
Step-by-step explanation:
Let the amount invested be $x and $y in both cases respectively
Since the total invested is $4,800
This means that;
x + y = 4800 ••••••••••••(i)
Now let’s have a look at the interests.
For the 9%
Interest would be 9/100 * amount invested
= 9/100 * x = 9x/100
For the 10%, interest would be
10/100 * y = 10y/100
Adding both will give a total of 457
9x/100 + 10y/100 = 457
multiply through by 100
9x + 10y = 45700 •••••••• (ii)
From equation i, we can write x = 4800 - y
we can substitute this into the second equation
9(4800-y) + 10y = 45700
43200 -9y + 10y = 45,700
43200 + y = 45,700
y = 45,700-43,200 = $2,500
Recall
x = 4800 -y
so x = 4800 -2500 = 2300
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