White also passed Acie Earl for the second-most points in school history to lead the Hawkeyes (21-10, 12-6 Big Ten).
Iowa never trailed in its final home game of the year. The Hawkeyes turned a six-point halftime lead into a 52-35 advantage midway through the second half and finished their conference slate with identical 6-3 home and road records.
Tre Demps had 15 points for Northwestern (15-16, 6-12), which lost for just the second time in seven games.
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