document.write( "Question 1181511: Dennis and Christine scored 32 and 23, respectively, in the National Career Assessment Examination (NCAE). The determining factor for a college scholarship is that a student's score should be in top 10% of the scores of his/her graduating class. The students in the graduating class obtained the following scores in the NCAE
\n" ); document.write( "Suppose that the given data is written in table
\n" ); document.write( "NCAE Scores f(frequency) LB \n" ); document.write( "39-41 6
\n" ); document.write( "36-38 7
\n" ); document.write( "33-35 9
\n" ); document.write( "30-32 13
\n" ); document.write( "27-29 22
\n" ); document.write( "24-26 10
\n" ); document.write( "21-23 9
\n" ); document.write( "18-20 7
\n" ); document.write( "15-17 8
\n" ); document.write( "12-14 4
\n" ); document.write( "9-11 2
\n" ); document.write( "6-8 1
\n" ); document.write( "3-5 1\r
\n" ); document.write( "\n" ); document.write( "Question
\n" ); document.write( "1. Complete the table by filling the LB or the lower boundaries and \n" ); document.write( "2. Find the 3rd quartile, 72nd percentile and the 8th decile of the set of data
\n" ); document.write( "3. What is the percentile rank of Dennis and Christine\r
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Algebra.Com's Answer #850006 by CPhill(1959)\"\" \"About 
You can put this solution on YOUR website!
Here's the solution:\r
\n" ); document.write( "\n" ); document.write( "**1. Completed Table:**\r
\n" ); document.write( "\n" ); document.write( "To find the lower boundaries (LB), subtract 0.5 from each lower class limit.\r
\n" ); document.write( "\n" ); document.write( "| NCAE Scores | f (frequency) | LB |
\n" ); document.write( "|-------------|---------------|-------|
\n" ); document.write( "| 39-41 | 6 | 38.5 |
\n" ); document.write( "| 36-38 | 7 | 35.5 |
\n" ); document.write( "| 33-35 | 9 | 32.5 |
\n" ); document.write( "| 30-32 | 13 | 29.5 |
\n" ); document.write( "| 27-29 | 22 | 26.5 |
\n" ); document.write( "| 24-26 | 10 | 23.5 |
\n" ); document.write( "| 21-23 | 9 | 20.5 |
\n" ); document.write( "| 18-20 | 7 | 17.5 |
\n" ); document.write( "| 15-17 | 8 | 14.5 |
\n" ); document.write( "| 12-14 | 4 | 11.5 |
\n" ); document.write( "| 9-11 | 2 | 8.5 |
\n" ); document.write( "| 6-8 | 1 | 5.5 |
\n" ); document.write( "| 3-5 | 1 | 2.5 |\r
\n" ); document.write( "\n" ); document.write( "**2. 3rd Quartile (Q3), 72nd Percentile (P72), and 8th Decile (D8):**\r
\n" ); document.write( "\n" ); document.write( "First, find the cumulative frequency (cf):\r
\n" ); document.write( "\n" ); document.write( "| NCAE Scores | f | cf |
\n" ); document.write( "|-------------|----|----|
\n" ); document.write( "| 39-41 | 6 | 88 |
\n" ); document.write( "| 36-38 | 7 | 82 |
\n" ); document.write( "| 33-35 | 9 | 75 |
\n" ); document.write( "| 30-32 | 13 | 66 |
\n" ); document.write( "| 27-29 | 22 | 53 |
\n" ); document.write( "| 24-26 | 10 | 31 |
\n" ); document.write( "| 21-23 | 9 | 21 |
\n" ); document.write( "| 18-20 | 7 | 12 |
\n" ); document.write( "| 15-17 | 8 | 5 |
\n" ); document.write( "| 12-14 | 4 | 1 |
\n" ); document.write( "| 9-11 | 2 | 1 |
\n" ); document.write( "| 6-8 | 1 | 1 |
\n" ); document.write( "| 3-5 | 1 | 1 |\r
\n" ); document.write( "\n" ); document.write( "* **Q3:** Q3 is the 75th percentile. (75/100) * 88 = 66. The 66th value falls in the 33-35 class.\r
\n" ); document.write( "\n" ); document.write( " Q3 = LB + [( (75/100) * N - cf_below ) / f_class ] * class_width
\n" ); document.write( " Q3 = 32.5 + [ (66 - 53) / 9 ] * 3
\n" ); document.write( " Q3 = 32.5 + 4.33 = 36.83\r
\n" ); document.write( "\n" ); document.write( "* **P72:** (72/100) * 88 = 63.36. The 63.36th value falls in the 30-32 class.\r
\n" ); document.write( "\n" ); document.write( " P72 = 29.5 + [(63.36 - 53) / 13] * 3
\n" ); document.write( " P72 = 29.5 + 2.41 = 31.91\r
\n" ); document.write( "\n" ); document.write( "* **D8:** (8/10) * 88 = 70.4. The 70.4th value falls in the 33-35 class.\r
\n" ); document.write( "\n" ); document.write( " D8 = 32.5 + [(70.4 - 53) / 9] * 3
\n" ); document.write( " D8 = 32.5 + 5.8 = 38.3\r
\n" ); document.write( "\n" ); document.write( "**3. Percentile Rank of Dennis and Christine:**\r
\n" ); document.write( "\n" ); document.write( "* **Dennis (score 32):** Dennis's score falls in the 30-32 class.\r
\n" ); document.write( "\n" ); document.write( " Percentile Rank = [ (cf_below + 0.5 * f_class) / N ] * 100
\n" ); document.write( " Percentile Rank = [ (53 + 0.5 * 13) / 88 ] * 100
\n" ); document.write( " Percentile Rank = [ (53 + 6.5) / 88 ] * 100
\n" ); document.write( " Percentile Rank = (59.5 / 88) * 100 ≈ 67.61\r
\n" ); document.write( "\n" ); document.write( "* **Christine (score 23):** Christine's score falls in the 21-23 class.\r
\n" ); document.write( "\n" ); document.write( " Percentile Rank = [ (21 + 0.5 * 9) / 88 ] * 100
\n" ); document.write( " Percentile Rank = [ (21 + 4.5) / 88 ] * 100
\n" ); document.write( " Percentile Rank = (25.5 / 88) * 100 ≈ 28.98
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