Working out the difference between the amount of wood available at the start and the end of the day shows that 10 bundles – 3 bundles = <<10-3=7>>7 bundles of wood have been burned throughout the day.
Subtracting the wood burned in the morning from this shows that 7 bundles – 4 bundles = <<7-4=3>>3 bundles of wood were burned in the afternoon.
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