The teacher asks Mel and Kate to use base 10 blocks to model the number that is ten times the value of 4 rods. Mel's modle uses 4 unit cubes. Kate's modle uses 4 flats. Which girl is correct?

Kate's model is correct because 10 times the value of 4 rods, 10 (4 (10)), is 400. Mel's model represents 4 (1) = 4, which is incorrect. Kate's model represents 4*100=400, which is correct.

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