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Here is this week’s problem:

From 2008 to 2009, the number of Easter eggs in a certain egg hunt rose 20%, then fell 17% from 2009 to 2010. From 2008 to 2009, the ratio of Easter eggs to Easter bunnies in the same hunt fell 20%, then rose 22% from 2009 to 2010. By what approximate percent did the number of bunnies change over the full period from 2008 to 2010?

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In 2008

Egg/Bunnies = x/y1= z

In 2009

Egg/Bunnies= 1.2x/y2 = 0.83z

Now change in bunnies will be given by

y2/y1 = 120/83

or in other words % increase in bunnies will be 50% from 2008 to 2009

Now in 2009

x/y1=z

in 2010

0.83x/y2=1.22z

Now change in bunnies will be given by

y2/y1 = 83/122

or in other words % decrease in bunnies will be 33% from 2009 to 2010

So if we assume that initially we have 100 bunnies, then first we have to increase it by 50% & then decrease by 33%

100 ——– 150 —— 103

Which leaves us a reply of 3% increase from 2008 to 2010