Final answer:
The exact percentage of black students attending all-black public schools in Los Angeles in 1970 is not provided. Historical context suggests that segregation was still an issue, reflecting nationwide patterns of racial separation in education despite desegregation efforts.
Step-by-step explanation:
The percentage of black students who attended all-black public schools in Los Angeles in 1970 is not directly stated in the provided text. However, it is clear from the historical context that school segregation was a prevalent issue nationwide, even after the 1954 Brown v. Board of Education decision. In other regions, we know that the segregation index was high, indicating a significant separation between black and white students in public schools. The situation for black students in Los Angeles likely reflected a broader nationwide challenge of segregation and unequal educational opportunities, despite the passing of civil rights legislation.
However, it is important to note that school segregation was not limited to Los Angeles or the South, as many Northern and Western communities also maintained segregated schools. Efforts to desegregate public schools led to a backlash, with some White parents enrolling their children in all-white private academies.