$\"\"$

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(a)

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The CPI in the year $\"\"$ is $\"\"$ .

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The CPI in the year $\"\"$ is $\"\"$ .

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Therefore, $\"\"$ and $\"\"$ .

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The time period is $\"\"$ .

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Find the average annual Inflation rate .

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The CPI index is $\"\"$ .

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Substitute all the values in above equation.

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$\"\"$

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$\"\"$

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$\"\"$

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$\"\"$

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$\"\"$

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$\"\"$

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$\"\"$

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Therefore,the average annual inflation rate is $\"\"$ .

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$\"\"$

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(b)

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what year will the CPI reach $\"\"$ .

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Substitute $\"\"$ and $\"\"$ and $\"\"$ in $\"\"$ .

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$\"\"$

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$\"\"$

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$\"\"$

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$\"\"$

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Take natural logarithm on each side.

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$\"\"$

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$\"\"$

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$\"\"$

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$\"\"$

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$\"\"$

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(a) The average annual inflation rate is $\"\"$ .

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(b)