MATHEMATICAL LITERACY GRADE 10 CAPS TOPIC 3 Measurement

MATHEMATICAL LITERACY GRADE 10 CAPS TOPIC 3: Measurement Section 3. 2: Measuring length and distance

Measurement The following sections will be covered: 3. 1 Conversions 3. 2 Measuring length and distance 3. 3 Measuring weight 3. 4 Measuring temperature 3. 5 Calculating perimeter and area 2

Measuring length and distance In section 3. 2, learners will be able to: �Determine length and/or distance using: o ‘rule of thumb’ method. o measuring instruments. o Trundle wheels o Odometers

Estimating length & distance using the Rule of thumb The rule of thumb: approximate/reliable method of estimating lengths/distances. Knowing the approximate lengths of our body parts enables us to estimate most lengths and distances. Ø The foot is approximately 30 cm Ø The thumb is approximately 2, 5 cm Ø A step is approximately 1 m Ø The distance from the shoulder to the fingertips of the outstretched opposite arm is about 1 m Ø Span from the tip of your thumb to the tip of your index finger Ø The length of your lower arm (from wrist to elbow) Ø Arm span across your body (from the tip of right hand index finger to the tip of left hand index finger)

Rule of thumb

Activity 1 Use your body measurements to estimate: 1. The length of your pen. 2. The width of the door in the classroom 3. The length of the classroom. 4. The thickness of textbook. 5. Measure the actual lengths of the lengths above and compare to your estimates.

Instruments for measuring length Short to medium lengths are measured using: Tape measures: different lengths 1, 5 m; 20 m; 100 m Ruler, and metre rule

Measuring length and distance Distances are longer lengths, they are measured using: � Trundle wheel: It is designed to cover 1 metre in a full turn, i. e. its circumference is 1 m. It is useful to measure distances that are not straight. �Odometers: are instruments fixed in vehicles, they measure the distance the vehicle moves in kilometres.

Trundle wheel & Odometer

Activity 2 1. What units and which tool will be most appropriate to measure: (a) The width of cellphone screen. (b) The length of the classroom. (c) The distance round the athletics track. (d) The distance from your home to school.

Solutions: Activity 2 (a) Unit: mm; Instrument: ruler or tape measure (b) Unit: m; Instrument: tape measure. (c) Unit: m; Instrument: trundle wheel. (d) Unit: km; Instrument: odometer.

Activity 3 1. Mike measures an access road with trundle wheel. What is the length of the road if the trundle wheel makes 125 complete turns? 2. What is the distance between point A and point B if a trundle wheel makes 22. 5 turns? 3. Before starting on a trip the driver of delivery truck noted that the odometer reading was 148 342 km, when he arrived at his destination, it was 148 937 km. How far did he travel?

Solutions: Activity 3 1. 125 m 2. 22, 5 m 3. Distance = 148 937 – 148 342 = 595 km

Final Assessment Questions 1 – 10 Question 1 What is the most suitable unit to measure the length of your workbook? A. km B. m C. cm D. mm

Question 2 What is the most suitable measuring instrument for measuring the distance around an athletics track? A. metre rule B. tape measure C. trundle wheel D. odometer

Question 3 The beginning and the end of the odometer reading of a journey are, 64 544 and 64 792 respectively. How long was the journey? A. 248 km B. 428 km C. 64 544 km D. 64 792 km

Question 4 Thato measures an access road with a trundle wheel. What is the length of the road if the trundle wheel made 1 050 complete turns? A. 1, 050 m B. 10, 50 m C. 105 m D. 1050 m

Question 5 Answer questions 5 – 8 using the distance table:

Question 5 The distance table on the previous slide gives you an indication of travel distances between various cities in South Africa. How many kilometres would you travel if you went from Durban to Underberg? A. 100 km B. 344 km C. 199 km D. 304 km

Question 6 Which city on the table is closest to Howick? A. Kokstad B. Hlohluwe C. Mooi River D. Pietermaritzburg

Question 7 Which city on the table is furthest away from Howick? A. Ulundi B. Vryheid C. Dundee D. Richards Bay

Question 8 Which is the quicker route from Durban to Kokstad, via Pietermaritzburg or via Port Shepstone? A. Via Port Shepstone B. Via Pietermaritzburg

Question 9 Violet ‘s normal step is about 1 m. She counts 123 steps from her home to the nearest Spaza Shop. What is the approximate distance from The spaza to her home? A. 123 mm B. 1230 cm C. 1, 23 m D. 0, 123 km

Solutions Final Assessment Questions 1. 2. 3. 4. 5. 6. 7. 8. 9. C C A D C D A A D