Three out of four Montgomery County ninth graders passed a statewide examination on citizenship and government that was administered this spring as part of a battery of tests all high school students now must pass in order to graduate, school officials said yesterday.

School Superintendent Wilmer S. Cody said he was "pleased with the results of the test," because all major racial and ethnic groups improved their performance compared with a similar, pilot test administered to county students last year.

The 75 percent who passed this year compared with 62 percent who passed the pilot test, officials said.

On a statewide basis, 58.6 percent of all Maryland ninth graders passed the latest test compared with 38 percent who took the pilot test, the officials said.

Black students in Montgomery showed the most improvement, a 20 percent gain in the number who passed this year, but they still trailed other racial and ethnic groups among those students that took the examination, officials said.

Eighty percent of white students passed, followed by 72 percent of Asian students, 58 percent of Hispanics and 56 percent of blacks.

Seventy-seven percent of the male students passed compared with 72 percent of the females, according to test results.

The citizenship exam, which tests students' knowledge of government and politics and of citizens' rights and responsibilities, is one of four functional exams administered by the state for the first time this year, with passing a requirement for graduation. The other exams cover reading, writing and mathematics.

On a school-by-school basis, ninth graders at Walt Whitman High in Bethesda led all other county secondary schools with a 93 percent passing rate.

Hoover Junior High in Rockville was second with 90 percent passing followed by Charles W. Woodward High in Rockville, which had an 87 percent passing rate.

All other schools exceeded the statewide passing rate, except Einstein High School in Kensington, where only 57 percent of the ninth graders passed. A school spokesman attributed the lower score to high turnover among teachers in the school's social studies department.