## Root problem

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### Root problem

by didieravoaka » Wed Mar 23, 2016 9:13 am
Does someone can help?

I don't understand why we have to multiple x by 3 for the first quarter. I thought it would have been an addition instead. So that we would have 3+x for the first quarter. At the 9th quarter we would have had 9x instead of 3x to the 9th power.

Thanks.

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by [email protected] » Wed Mar 23, 2016 9:19 am
Hi didieravoaka,

We're told that every quarter-century (meaning every 25 years), the price of a bushel is X TIMES (meaning multiplication) more expensive. From 1775 to 2000, we have nine 25-year 'periods' in which the bushel becomes X TIMES more expensive with each period, so we're clearly talking about a LOT of multiplication. However, the price in 1775 is $3 and the price in 2000 is only$9, so all of that multiplication leads to a total product that is only 3 times more expensive over the course of 9 periods. There's only one answer that has a 3 AND accounts for 9 'periods'...