The Consumer Price (CPI) of one particular country can be modeled by I(t)=−0.555t3+0.82t2+1.17t+528(0≤ t≤10) where t is time in months since the start of January 2015. What was the inflation rate in July 2015 (t=6)? Round your percent to decimal places.

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The Consumer Price (CPI) of one particular country can be modeled by I(t)=−0.555t3+0.82t2+1.17t+528(0≤ t≤10) where t is time in months since the start of January 2015.  What was the inflation rate in July 2015 (t=6)? Round your percent to  decimal places.

SchepperJ · Accepted Answer

Step 1  Given CPI of a country,  I(t)=−0.055t3+0.82t2+1.17t+528  Where t is number of months since start of January 2015.  And 0≤ t≤10  To find inflation rate in July, 2015 that is when t=6  Step 2  Initial rate, IR=I(0)  ⇒ IR=−0.055(0)3+0.82(0)2+1.17(0)+528  ⇒ IR=528  And final rate, FR=I(6)  ⇒ FR=−0.055(6)3+0.82(6)2+1.17(6)+528  =−11.88+29.52+7.02+528  ⇒ FR=552.66  Since FR&amp;gt;IR  ⇒ The inflation rate is positive.  IR=[FV−IVIV]×100  =[552.66−528528]×100  =4.67045455  Hence the inflation rate is 4.67  (Rounded to two decimals)

The Consumer Price (CPI) of one particular country can be modeled by I(t)=-0.555t^{3}+0.82t^{2}+1.17t+528(0\leq\ t\leq10) where t is time in months since the start of January 2015. What was the inflation rate in July 2015 (t=6)? Round your percent to decimal places.

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