You can
put this solution on YOUR website!Let L be number of libraries in 2000
---Solution#1:
(Number libraries in 2007) = (number of livraries in 2000)+ (75% increase)
350 = L + 0.75L
Now solve for L
---Solution#2:
Another way to thinking is you have system that's change from one condition (state) to another.
The change from State#1 to State#2 is +75% compared State#1.
For example:
L1=number of libraries in 2005
L2=number of libraries in 2007 = 350
If you rewrite it's the same equation as the Solution#1.
But thinking this way can help with other future subjects like chem or physics, when they start talking about systems changing.
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