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MATH / Derek's phone number, 336 - 7624, has the property that the three-digit prefix, 336, equals the product of the last four digits, 7×6×2×4. How many seven-digit phone numbers beginni… · Discussion

Discussing Derek's phone number, 336 - 7624, has the property that the three-digit prefix, 336, equals the product of the last four digits, 7×6×2×4. How many seven-digit phone numbers beginni… · MATH

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