132 is rounded to the 130 cause you just look at the last number and you see what is the closes zero that's why it is 130
Nothing more can be done to this problem, it stays the same.
if we divide 16 by 8000, we get 0.002
Times 0.002 with 100, and you will get your percent
0.002*100=0.2
16 is 0.2% of 8000
Let x=annual interest rate of 18000 investment.
Then
18000*x - 9000(x-0.006)=648
Solve for x
18000x-9000x+9000*0.006=648
9000x=648-54=594
x=594/9000=0.066
Answer:
the annual interest rate of the 18000 investment is 6.6%
the annual interest rate of the 9000 investment is 6.0%