problem solving
posted by Anonymous .
a stack of firewood has 28 pieces on the bottom row,24 on the top of those,then 20 ,and so on.If there are 108 pieces of wood.How many rows are there?

well you could solve it the long way
28
24
20
16
12
8
4
add um all up=112
108 is 4 less so subtract the last row,
6 rows
there is some equation that is soposed to be faster, but seeing as all that took me 40 seconds aprox. WELL
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