| Time, \(t\) | Number of students |
| 10-19 | 2 |
| 20-29 | 4 |
| 30-39 | 8 |
| 40-49 | 11 |
| 50-69 | 5 |
| 70-79 | 2 |
| \(x\) | 1 | 2 | 3 | 4 |
| \(\mathrm { P } ( X = x )\) | \(k\) | \(2 k\) | \(3 k\) | \(4 k\) |
| \(y\) | 2 | 3 | 4 | 5 | 6 | 7 | 8 |
| \(\mathrm { P } \left( X _ { 1 } + X _ { 2 } = y \right)\) | 0.01 | 0.04 | 0.10 | 0.25 | 0.24 |
| Delay (minutes) | Number of motorists |
| 4-6 | 6 |
| 7-8 | |
| 9 | 21 |
| 10-12 | 45 |
| 13-15 | 9 |
| 16-20 |
| \(x\) | 2 | 3 | 4 | 6 |
| \(\mathrm { P } ( X = x )\) | \(\frac { 5 } { 21 }\) | \(\frac { 2 k } { 21 }\) | \(\frac { 7 } { 21 }\) | \(\frac { k } { 21 }\) |
| Mark | Totals | ||
| 3 | 699 | 9 | \(( 3 )\) |
| 4 | 012223 | 4 | \(( 6 )\) |
| 4 | 566668 | \(( 5 )\) | |
| 5 | 0233344 | \(( 6 )\) | |
| 5 | 5566779 | \(( 6 )\) | |
| 6 | 00000013444 | \(( 9 )\) | |
| 6 | 5566789 | \(( 6 )\) | |
| 7 | 12333 | \(( 4 )\) |
| Key | (3|6 means 36) |
| \(t { } ^ { \circ } \mathrm { C }\) | 8 | 13 | 14 | 15 | 15 | 20 | 25 | 30 |
| \(m\) secs | 6.5 | 4.5 | 6 | 5 | 4 | 3 | 2 | 1 |
| Income \(y\) (£) | Mid-point | Frequency \(f\) |
| \(0 \leqslant y < 200\) | 100 | 12 |
| \(200 \leqslant y < 240\) | 220 | 28 |
| \(240 \leqslant y < 320\) | 280 | 22 |
| \(320 \leqslant y < 400\) | 360 | 18 |
| \(400 \leqslant y < 600\) | 500 | 12 |
| \(600 \leqslant y < 800\) | 700 | 8 |
| \(r\) | 2 | 4 | 6 |
| \(\mathrm { P } ( R = r )\) | \(\frac { 2 } { 3 }\) | \(\frac { 1 } { 6 }\) | \(\frac { 1 } { 6 }\) |
| \(x\) | - 2 | - 1 | 0 | 1 | 2 | 3 |
| \(\mathrm { P } ( X = x )\) | 0.1 | \(\alpha\) | 0.3 | 0.2 | 0.1 | 0.1 |
| Lengths | 20 means 20 | |
| 2 | 0122 | \(( 4 )\) |
| 2 | 55667789 | \(( 7 )\) |
| 3 | 012224 | \(( 5 )\) |
| 3 | 566679 | \(( 5 )\) |
| 4 | 01333333444 | \(( 10 )\) |
| 4 | 5556667788999 | \(( 12 )\) |
| 5 | 000 | \(( 3 )\) |
| Diane | Gopal | |
| Smallest value | 35 | 25 |
| Lower quartile | 37 | 34 |
| Median | 42 | 42 |
| Upper quartile | 53 | 50 |
| Largest value | 65 | 57 |
| \(x\) | 12 | 15 | 7 | 11 | 1 | 8 | 4 | 6 | 9 | 3 |
| \(y\) | 8 | 4 | 13 | 8 | 18 | 12 | 15 | 14 | 12 | 16 |