Answer: They had a larger cavalry than the Persians.
The Greeks held an advantage at Marathon in the equipment of their infantry. An Athenian hoplite carried a heavy, 9-foot spear, wore a solid breastplate, and carried an almost body-length shield. The Persian infantryman, in contrast, wore little more than robes and carried a shorter sword and a wicker or cane shield.
Step-by-step explanation:
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