The table below shows changes in the population densities of the zebra and you knew I'd muscles from 1991 to 2015, in six-year intervals.
1. Based on the data shown in the table calculate the percent change in the population density of zebra mussels from 1997 to 2003
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1997 (3 250)
2003 (2 500)
Percentage change= 100 *(new value- old value)/old value
Percentage change = 100 *(2500- 3250)/ 3250 = 100* (-0.2308)
Percentage change = -23.08%
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Answer
The percent change in the population density of zebra mussels from 1997 to 2003 is -23.08%
There was a decrease of 23. 08%