Answer :
The rate of change of this simple index over 1 week is - 8.81%
What is the rate of change ?
The rate of change is the ratio of the difference in the value of the simple index to the original value of simple index.
Total value of the simple index at day 1 = (8000 x $4.25) + (5000 x $2.90) + (2000 x $6.40) = $61,300
Total value of the simple index at day 8 = (8000 x $3.90) + (5000 x $2.50)+(2000*6.10) = 55900
the rate of change of this simple index over 1 week
= (55900-61300)/ 61300 * 100 %
= -8.81 %
the rate of change of this simple index over 1 week is - 8.81%
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