A carpenter is building a house. He needs 80 woodblocks to build it. If he has 8 logs that can make five woodblocks each, how many logs does the carpenter still need?
The carpenter initially has 8 x 5 = <<8*5=40>>40 blocks of wood.
So he still lacks 80 - 40 = <<80-40=40>>40 blocks of wood.
Therefore he still needs 40 / 5 = <<40/5=8>>8 logs of wood.
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