Characteristics of the medium response:

Questions 1 through 4 of Parts 1 and 2 are answered satisfactorily — that is, a pattern has been noted and extended to the bridges that are too long to construct with the available rods.

Questions 5 and 6, however, are not answered appropriately; the general rule may be unclear or not universally applicable.

In Part 2, if the division of 429/7 is done using a calculator (or with pencil and paper), the resulting decimal is reported without rounding up to the next whole number.

Characteristics of the low response:

Questions 1 and 2 of Parts 1 and 2 are answered satisfactorily, although the child may have to build the 5-span bridges and count the rods before responding.

More generally, though, the low response indicates an incomplete grasp of the relationships among (a) the length of each span rod, (b) the number of spans, and (c) the total length of the bridge.

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