Worked example · PE · Year 7
LNF: Numeracy → Learning about geometry helps us understand shape, space and position, and learning about measurement helps us quantify in the real world → Measurement
A secure Year 7 response, annotated so you can see which success criterion each part meets. It is also the answer key. Winners: Efa (100 m, 14.07 s), Iwan (800 m, 169.7 s), Osian (long jump, 360 cm) and Tawel House (relay, 60.0 s, by 1.3 s).
01:02.35 means 1 minute, 2 seconds and 35 hundredths of a second. In seconds: 60 + 2.35 = 62.35 seconds.
Each part of the display is read correctly and changed into one unit. Evidences criterion 1.
| Place | 1st | 2nd | 3rd | 4th | 5th | 6th |
|---|---|---|---|---|---|---|
| Runner | Efa | Alys | Cerys | Beca | Ffion | Dyddgu |
| Time (s) | 14.07 | 14.62 | 14.90 | 15.08 | 15.50 | 16.30 |
(b) No. 14.9 is the same as 14.90, and 14.90 is between 14.62 and 15.08. The number of digits after the point does not tell you the size. Cerys came 3rd.
(c) 14.62 − 14.07 = 0.55 s. 16.30 − 14.07 = 2.23 s.
Every time is written to 2 decimal places before ordering, which avoids the 14.9 trap. Evidences criteria 2 and 4.
| Runner | Stopwatch | Working | Seconds |
|---|---|---|---|
| Gethin | 02:58.40 | 2 × 60 = 120, 120 + 58.4 | 178.4 |
| Huw | 03:05.00 | 3 × 60 = 180, 180 + 5.0 | 185.0 |
| Iwan | 02:49.70 | 120 + 49.7 | 169.7 |
| Jac | 03:21.30 | 180 + 21.3 | 201.3 |
| Llŷr | 02:59.60 | 120 + 59.6 | 179.6 |
Order: Iwan, Gethin, Llŷr, Huw, Jac.
178.4 − 169.7 = 8.7 s. 201.3 − 169.7 = 31.6 s.
Minutes are converted to seconds before comparing. Gethin and Llŷr are only 1.2 s apart, which is easy to get wrong without converting. Evidences criteria 3 and 4.
| Jumper | As written | Centimetres | Metres | Place |
|---|---|---|---|---|
| Mali | 3.45 m | 345 cm | 3.45 m | 3rd |
| Nia | 3 m 8 cm | 308 cm | 3.08 m | 5th |
| Osian | 3.6 m | 360 cm | 3.60 m | 1st |
| Pryderi | 342 cm | 342 cm | 3.42 m | 4th |
| Rhian | 3 m 51 cm | 351 cm | 3.51 m | 2nd |
3.8 m is 3 m 80 cm, not 3 m 8 cm. 8 cm is 8 hundredths of a metre, so it is written 3.08 m.
Each jump is recorded in two ways, and the place-value mistake in 3.8 m is explained. Evidences criteria 2 and 3.
(a) 15.2 + 14.8 + 15.6 + 14.4 = 60.0 s = 1 minute exactly.
(b) Dyffryn House: 01:01.30 = 61.3 s. Tawel House won by 61.3 − 60.0 = 1.3 s.
Both totals are in the same unit before they are compared. Evidences criteria 1 and 4.
| Measurement | Best unit |
|---|---|
| A 100 m sprint final | hundredths of a second |
| A 1,500 m race | minutes and seconds |
| A 21 km charity fun run | hours and minutes |
| A long jump | centimetres (or metres to 2 decimal places) |
| How far a javelin is thrown | metres |
| How long a plank is held | seconds |
In a sprint, runners often finish very close together, so hundredths of a second are needed to separate them. In a fun run, people finish minutes apart and nobody needs to know a time that precisely.
The unit is matched to how long the event lasts and how close the results are. Evidences criterion 5.
Lap time: 169.7 ÷ 2 = 84.85 s, which is 1 minute 24.85 seconds.
Long jump range: 360 − 308 = 52 cm.
Between Gethin and Llŷr: any time between 02:58.40 and 02:59.60, for example 02:59.00 (179.0 s).