Yes, I passed the test.

No, it really wasn't hard.

But it wasn't absurdly easy, either, even though I missed only one of its 159 questions.

To thousands of Virginia high school students, the test, called a graduation competency exam, means one more hurdle -- on top of the usual courses and grades -- to earning their high school diplomas.

To Virginia legislators who voted last year to require the test, it is one way the public has to make sure students have mastered at least some basic skills before they are certified as high school graduates.

But how basic are the skills? How hard is the test?

On Wednesday, the State Education Department reported that 18 percent of Virginia's 10th graders failed to achieve a passing score of 70 on both parts of the exam in reading and mathematics.

Despite requests by reporters and a local court ruling in Richmond, the test itself is still secret because officials say they plan to use many of its questions again. But some sample questions have been distributed, as well as a few from the test itself that will not be repeated. Reporters have been allowed to take the exam, though they must pledge secrecy about exactly what the questions ask.

The test has no time limit and I worked slowly -- partly in response to official advice and partly to avoid the embarrassment of scoring low. The 99 questions in mathematics took me about an hour to answer; the 60 questions in reading took about 50 minutes.

All of the questions are multiple-choice; all of the answers must be marked on a separate sheet by filling in the right circles with a pencil.

That's how I made my one mistake. It was a question about the perimeter of a square, which required adding up the length of its four sides or simply multiplying one side by four. I did that just fine, but then filled in the wrong circle on the answer sheet.

Oh, well, clerical error.

The questions ranged from the very easy to the fairly difficult, I thought. Only a few required much insight. Many required a clerk's careful attention to detail. Some tested plain academic skills that schools have traditionally taught, like adding fractions, figuring percentages and using a dictionary. Others put school skills to practical use in "real world" situations, such as making change, using a telephone book and figuring out what a worker takes home after taxes have been deducted from his paycheck.

The mathematics part of the exam, which I took first, starts with some very simple questions. There were three about reading a thermometer, a skill that Virginia schools are supposed to teach to second graders according to a state education department directive. There were also two problems in simple multiplication, which is taught in third grade.

But at the end of the exam there were six questions about writing a check and balancing a checkbook, skills that many schools do not teach, though a state education official said he expects they are going to do so now. There also were questions based on an income tax table, exactly like the one millions of taxpayers will wrestle with in April.

Between these extremes students had to figure sales taxes and discounts, and determine which size package is the cheapest from an array of toothpaste tubes and cereal boxes.

One-third of the reading exam is based on warnings like those usually printed on medicine bottles and boxes of household detergent. Simple situations are described and students are asked whether the person involved did the right thing, based on the warning. Then there were questions about finding the main idea in a series of brief passages and filling out forms, including applications for jobs, credit cards, loans and insurance.

The hardest reading questions, according to state education officials, are ones that require students to read a document of some sort, dealing for instance with consumer rights or filing a discrimination complaint, and then using it to take action. That requires grasping a problem and paying attention to details, as well as reading all the words correctly.

"This is a test to measure minimum competency," explained assistant superintendent Richard L. Boyer. "It's a floor. That's all it is. But if students can't do these things, they're likely to have problems."

I think that sums the test up well.