Mathematics 10 — Exercise Review · Q2
Full question
The table gives long-jump distances in centimetres. Construct the cumulative-frequency polygon and determine the median, Q₁, Q₃, D₇, P₉₀ and interquartile range.
| Class boundaries | Frequency |
|---|---|
| 170–180 | 2 |
| 180–190 | 6 |
| 190–200 | 9 |
| 200–210 | 12 |
| 210–220 | 8 |
| 220–230 | 3 |
Step-by-step solution
Cumulative frequency means a running total. Begin with zero at the first lower boundary.
Class 170–180: add frequency 2 to the preceding total.
Class 180–190: add frequency 6 to the preceding total.
Class 190–200: add frequency 9 to the preceding total.
Class 200–210: add frequency 12 to the preceding total.
Class 210–220: add frequency 8 to the preceding total.
Class 220–230: add frequency 3 to the preceding total.
Plot each UPPER boundary against its cumulative frequency, and join adjacent points.
Median: find the cumulative-frequency position 1/2×40.
Calculate this operation before combining the remaining terms.
Keep the common denominator and add the signed numerators.
Calculate this operation before combining the remaining terms.
Median lies between cumulative totals 17 and 29. Interpolate along that graph segment: lower boundary + (position−previous total)/class frequency × class width.
Calculate this operation before combining the remaining terms.
Calculate this operation before combining the remaining terms.
Calculate this operation before combining the remaining terms.
For multiplication of fractions, multiply the numerators together and the denominators together.
Calculate these two products separately.
The numerator and denominator have this greatest common divisor. Divide BOTH by it.
For multiplication of fractions, multiply the numerators together and the denominators together.
Calculate these two products separately.
Show the two divisions explicitly.
Write the reduced fraction.
Calculate this operation before combining the remaining terms.
For multiplication of fractions, multiply the numerators together and the denominators together.
Calculate these two products separately.
Show the two divisions explicitly.
Write the reduced fraction.
Calculate this operation before combining the remaining terms.
For multiplication of fractions, multiply the numerators together and the denominators together.
Calculate this operation before combining the remaining terms.
Show the two divisions explicitly.
Evaluate the numerator division.
Evaluate the denominator division.
Write the reduced fraction.
For multiplication of fractions, multiply the numerators together and the denominators together.
Calculate these two products separately.
Calculate this operation before combining the remaining terms.
Calculate this operation before combining the remaining terms.
Calculate this operation before combining the remaining terms.
Calculate this operation before combining the remaining terms.
For multiplication of fractions, multiply the numerators together and the denominators together.
Calculate this operation before combining the remaining terms.
For multiplication of fractions, multiply the numerators together and the denominators together.
Calculate these two products separately.
The numerator and denominator have this greatest common divisor. Divide BOTH by it.
For multiplication of fractions, multiply the numerators together and the denominators together.
Calculate these two products separately.
Show the two divisions explicitly.
Evaluate the denominator division.
Write the reduced fraction.
Calculate this operation before combining the remaining terms.
For multiplication of fractions, multiply the numerators together and the denominators together.
Calculate these two products separately.
Show the two divisions explicitly.
Write the reduced fraction.
Calculate this operation before combining the remaining terms.
For multiplication of fractions, multiply the numerators together and the denominators together.
Calculate this operation before combining the remaining terms.
Show the two divisions explicitly.
Evaluate the numerator division.
Evaluate the denominator division.
Write the reduced fraction.
Calculate this operation before combining the remaining terms.
To add these fractions, first use a common denominator: the least common multiple of their denominators.
Multiply this numerator AND denominator by the same factor. Its value stays unchanged.
Calculate the converted numerator; the denominator is now common.
Multiply this numerator AND denominator by the same factor. Its value stays unchanged.
Calculate the converted numerator; the denominator is now common.
Calculate this operation before combining the remaining terms.
For multiplication of fractions, multiply the numerators together and the denominators together.
Calculate these two products separately.
Calculate this operation before combining the remaining terms.
Keep the common denominator and add the signed numerators.
Calculate this operation before combining the remaining terms.
Median ≈ 202.500.
Q1: find the cumulative-frequency position 1/4×40.
Calculate this operation before combining the remaining terms.
Keep the common denominator and add the signed numerators.
Calculate this operation before combining the remaining terms.
Q1 lies between cumulative totals 8 and 17. Interpolate along that graph segment: lower boundary + (position−previous total)/class frequency × class width.
Calculate this operation before combining the remaining terms.
Calculate this operation before combining the remaining terms.
Calculate this operation before combining the remaining terms.
For multiplication of fractions, multiply the numerators together and the denominators together.
Calculate these two products separately.
For multiplication of fractions, multiply the numerators together and the denominators together.
Calculate these two products separately.
Calculate this operation before combining the remaining terms.
Calculate this operation before combining the remaining terms.
Calculate this operation before combining the remaining terms.
Calculate this operation before combining the remaining terms.
For multiplication of fractions, multiply the numerators together and the denominators together.
Calculate this operation before combining the remaining terms.
For multiplication of fractions, multiply the numerators together and the denominators together.
Calculate these two products separately.
Calculate this operation before combining the remaining terms.
To add these fractions, first use a common denominator: the least common multiple of their denominators.
Multiply this numerator AND denominator by the same factor. Its value stays unchanged.
Calculate the converted numerator; the denominator is now common.
Multiply this numerator AND denominator by the same factor. Its value stays unchanged.
Calculate the converted numerator; the denominator is now common.
Calculate this operation before combining the remaining terms.
For multiplication of fractions, multiply the numerators together and the denominators together.
Calculate these two products separately.
Calculate this operation before combining the remaining terms.
Keep the common denominator and add the signed numerators.
Calculate this operation before combining the remaining terms.
Q1 ≈ 192.222.
Q3: find the cumulative-frequency position 3/4×40.
Calculate this operation before combining the remaining terms.
Keep the common denominator and add the signed numerators.
Calculate this operation before combining the remaining terms.
Q3 lies between cumulative totals 29 and 37. Interpolate along that graph segment: lower boundary + (position−previous total)/class frequency × class width.
Calculate this operation before combining the remaining terms.
Calculate this operation before combining the remaining terms.
Calculate this operation before combining the remaining terms.
For multiplication of fractions, multiply the numerators together and the denominators together.
Calculate these two products separately.
Calculate this operation before combining the remaining terms.
Calculate this operation before combining the remaining terms.
For multiplication of fractions, multiply the numerators together and the denominators together.
Calculate this operation before combining the remaining terms.
For multiplication of fractions, multiply the numerators together and the denominators together.
Calculate these two products separately.
The numerator and denominator have this greatest common divisor. Divide BOTH by it.
For multiplication of fractions, multiply the numerators together and the denominators together.
Calculate these two products separately.
Show the two divisions explicitly.
Calculate this operation before combining the remaining terms.
For multiplication of fractions, multiply the numerators together and the denominators together.
Calculate this operation before combining the remaining terms.
Show the two divisions explicitly.
Evaluate the numerator division.
Evaluate the denominator division.
Write the reduced fraction.
Calculate this operation before combining the remaining terms.
To add these fractions, first use a common denominator: the least common multiple of their denominators.
Multiply this numerator AND denominator by the same factor. Its value stays unchanged.
Calculate the converted numerator; the denominator is now common.
Multiply this numerator AND denominator by the same factor. Its value stays unchanged.
Calculate the converted numerator; the denominator is now common.
Calculate this operation before combining the remaining terms.
For multiplication of fractions, multiply the numerators together and the denominators together.
Calculate these two products separately.
Calculate this operation before combining the remaining terms.
Keep the common denominator and add the signed numerators.
Calculate this operation before combining the remaining terms.
Q3 ≈ 211.250.
D7: find the cumulative-frequency position 7/10×40.
Keep the common denominator and add the signed numerators.
Calculate this operation before combining the remaining terms.
D7 lies between cumulative totals 17 and 29. Interpolate along that graph segment: lower boundary + (position−previous total)/class frequency × class width.
Calculate this operation before combining the remaining terms.
Calculate this operation before combining the remaining terms.
For multiplication of fractions, multiply the numerators together and the denominators together.
Calculate these two products separately.
Calculate this operation before combining the remaining terms.
Calculate this operation before combining the remaining terms.
Calculate this operation before combining the remaining terms.
For multiplication of fractions, multiply the numerators together and the denominators together.
Calculate this operation before combining the remaining terms.
For multiplication of fractions, multiply the numerators together and the denominators together.
Calculate these two products separately.
The numerator and denominator have this greatest common divisor. Divide BOTH by it.
For multiplication of fractions, multiply the numerators together and the denominators together.
Calculate these two products separately.
Show the two divisions explicitly.
Write the reduced fraction.
Calculate this operation before combining the remaining terms.
For multiplication of fractions, multiply the numerators together and the denominators together.
Calculate these two products separately.
Show the two divisions explicitly.
Write the reduced fraction.
Calculate this operation before combining the remaining terms.
For multiplication of fractions, multiply the numerators together and the denominators together.
Calculate this operation before combining the remaining terms.
Show the two divisions explicitly.
Evaluate the numerator division.
Evaluate the denominator division.
Write the reduced fraction.
Calculate this operation before combining the remaining terms.
To add these fractions, first use a common denominator: the least common multiple of their denominators.
Multiply this numerator AND denominator by the same factor. Its value stays unchanged.
Calculate the converted numerator; the denominator is now common.
Multiply this numerator AND denominator by the same factor. Its value stays unchanged.
Calculate the converted numerator; the denominator is now common.
Calculate this operation before combining the remaining terms.
For multiplication of fractions, multiply the numerators together and the denominators together.
Calculate these two products separately.
Calculate this operation before combining the remaining terms.
Keep the common denominator and add the signed numerators.
Calculate this operation before combining the remaining terms.
D7 ≈ 209.167.
P90: find the cumulative-frequency position 9/10×40.
Keep the common denominator and add the signed numerators.
Calculate this operation before combining the remaining terms.
P90 lies between cumulative totals 29 and 37. Interpolate along that graph segment: lower boundary + (position−previous total)/class frequency × class width.
Calculate this operation before combining the remaining terms.
Calculate this operation before combining the remaining terms.
For multiplication of fractions, multiply the numerators together and the denominators together.
Calculate these two products separately.
Calculate this operation before combining the remaining terms.
Calculate this operation before combining the remaining terms.
For multiplication of fractions, multiply the numerators together and the denominators together.
Calculate this operation before combining the remaining terms.
For multiplication of fractions, multiply the numerators together and the denominators together.
Calculate these two products separately.
The numerator and denominator have this greatest common divisor. Divide BOTH by it.
For multiplication of fractions, multiply the numerators together and the denominators together.
Calculate these two products separately.
Show the two divisions explicitly.
Write the reduced fraction.
Calculate this operation before combining the remaining terms.
For multiplication of fractions, multiply the numerators together and the denominators together.
Calculate this operation before combining the remaining terms.
Show the two divisions explicitly.
Evaluate the numerator division.
Evaluate the denominator division.
Write the reduced fraction.
Calculate this operation before combining the remaining terms.
To add these fractions, first use a common denominator: the least common multiple of their denominators.
Multiply this numerator AND denominator by the same factor. Its value stays unchanged.
Calculate the converted numerator; the denominator is now common.
Multiply this numerator AND denominator by the same factor. Its value stays unchanged.
Calculate the converted numerator; the denominator is now common.
Calculate this operation before combining the remaining terms.
For multiplication of fractions, multiply the numerators together and the denominators together.
Calculate these two products separately.
Calculate this operation before combining the remaining terms.
Keep the common denominator and add the signed numerators.
Calculate this operation before combining the remaining terms.
P90 ≈ 218.750.
For multiplication of fractions, multiply the numerators together and the denominators together.
Calculate these two products separately.
Calculate this operation before combining the remaining terms.
Interquartile range is Q3−Q1.
To add these fractions, first use a common denominator: the least common multiple of their denominators.
Multiply this numerator AND denominator by the same factor. Its value stays unchanged.
Calculate the converted numerator; the denominator is now common.
For multiplication of fractions, multiply the numerators together and the denominators together.
Calculate this operation before combining the remaining terms.
Multiply this numerator AND denominator by the same factor. Its value stays unchanged.
For multiplication of fractions, multiply the numerators together and the denominators together.
The numerator and denominator have this greatest common divisor. Divide BOTH by it.
Show the two divisions explicitly.
Evaluate the numerator division.
Evaluate the denominator division.
Calculate this operation before combining the remaining terms.
Calculate the converted numerator; the denominator is now common.
Calculate this operation before combining the remaining terms.
Calculate this operation before combining the remaining terms.
For multiplication of fractions, multiply the numerators together and the denominators together.
Calculate these two products separately.
Calculate this operation before combining the remaining terms.
Keep the common denominator and add the signed numerators.
Calculate this operation before combining the remaining terms.
| Class | f | Cumulative f |
|---|---|---|
| 170–180 | 2 | 2 |
| 180–190 | 6 | 8 |
| 190–200 | 9 | 17 |
| 200–210 | 12 | 29 |
| 210–220 | 8 | 37 |
| 220–230 | 3 | 40 |
Answer
Median ≈ 202.5; Q1 ≈ 192.222; Q3 ≈ 211.25; D7 ≈ 209.167; P90 ≈ 218.75; IQR ≈ 19.028