WASHINGTON — The U.S. Department of Education announced it will withhold $350 million of congressionally approved funds to minority-serving colleges and universities and divert the funds elsewhere, saying that the institutions’ admissions quotas are discriminatory. The schools affected by Wednesday’s announcement are Alaska Native and Native Hawaiian-serving institutions; Black institutions; Asian American and Native American Pacific Islander-serving institutions; Native American-serving nontribal institutions; and institutions receiving Minority Science and Engineering Improvement grants. Roughly 5 million students are enrolled in the more than 800 minority-serving institutions across the country. The schools aim to help students of color and students from low-income backgrounds pursue higher education. Most minority-serving institutions, about 70%, are Hispanic-serving institutions, according to Rutgers University’s Center for Minority Serving Institutions.