On a placement examination, Rick scored lower than 1144 of the 12,900 students who took the exam. Find the percentile, rounded to the nearest percent, for Rick's score. Rick was at the st percentile.

Step 1 ：On a placement examination, Rick scored lower than 1144 of the 12,900 students who took the exam. We are asked to find the percentile, rounded to the nearest percent, for Rick's score.

Step 2 ：The percentile of a score is the percentage of scores that are less than or equal to that score. In this case, we know that Rick scored lower than 1144 students out of 12900.

Step 3 ：To find the percentile, we can use the formula: Percentile = \( \frac{Number\ of\ scores\ less\ than\ the\ score}{Total\ number\ of\ scores} \times 100 \)

Step 4 ：In this case, the number of scores less than Rick's score is 1144 and the total number of scores is 12900. We can plug these values into the formula to find the percentile.

Step 5 ：Substituting the given values into the formula, we get: Percentile = \( \frac{1144}{12900} \times 100 \)

Step 6 ：Calculating the above expression, we get the percentile as approximately 8.868217054263566

Step 7 ：Rounding this to the nearest percent, we get 9

Step 8 ：Final Answer: Rick was at the \( \boxed{9} \)th percentile.