Answer:
300
Step-by-step explanation:
The larger block can be cut into 7 cm pieces for a total of 10 pieces along the 72 cm dimension, 6 pieces along the 42 cm dimension, and 5 pieces along the 36 cm dimension. That will yield a total of
10 × 6 × 5 = 300 . . . cubical blocks
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Remaining scraps could be fastened together to make additional blocks.