General
Unit 5 : Length measurements
5. 0 Preliminary activities
Activity 5.0.1
Activity 5.0.2
Activity 5.0.3
Activity 5.0.4
Activity 5.0.5
Solve word problems
1. The chalkboard of our classroom has the length of 8m.
The chalkboard of the neighboring classroom has the length of 6m. Find the total length of the two chalkboards.
2. Kaneza’s garden has a length of 20 m. The garden of Mitari measures 18m. What is the total length for the two gardens?3. On Monday, Mariza bought 14m of pieces of clothe. On Tuesday, she bought 13 m of the same cloth.
The next day she bought 12m. Find the total length for the pieces of clothes she bought.
4. Mayira has a rope of 10m. His brother’s rope has 19 dm. What is the total length for the two ropes?
5. Nshuti made a mat of 20 dm. Her sister Mutesi made a mat of 17 dm. What is the difference in the length of the two mats?
6. I made a rope of 72m. My father cut 12m from it to tie the banana plant and protect it against strong wind.
What is the length of the remaing rope?
7. Munezero has a timber of 12m. Kagabo’s timber measures 8 m. What is the total length for the two timbers?
5.1 Measuring the length of objects using a meter ruler
Activity 5.1
Do the following activity in groups :
1. Use a meter ruler and measure:
(a) The length of your desk
(b) The length of teacher’s table
2. Use a meter ruler and measure:
(a) The width of the teacher’s cupboard
(b) The width or the height of your blackboard
3. Use a meter ruler and measure: the perimeter of your classroom.
4. Use a meter ruler and measure:
(a) The width of your classroom door .
(b) The total length of two sides (length) of your classroom
5. Use a 30cm ruler and measure the length of notebooks and books, and other objects in your classrooms.
5.2 Dividing a meter into 10 equal parts
Activity 5.2
Do the following activities:
1. Get sugar cane of 1m long. Divide this cane in 10 equal parts.
2. Get a rope of 1m long. Cut it in 10 equal parts.
3. Get a thread of 1m long. Divide it in 10 parts of the same length.
4. Get a cloth measuring 1m long. Cut it in 10 equal parts.
5.3 Dividing a decimeter into 10 equal parts
Activity 5.3
In your groups do the following activities:
1. Take a rope of 1dm. Cut it in 10 equal parts.
2. Take a small tree of 1m. Divide it in 10 parts of the same length.
5.4 Conversion of Units of length
Activity 5.4.1
5.5 Comparing lengths
Activity 5.5
5.6 Measuring the length round objects
Activity 5.6
1. Use a meter ruler and measure the total length round your classroom.
2. Measure the length of 10 m in the playground.
3. Use a meter ruler and measure the length round a garden
4. Use a rope of 10 m to measure the length round the football pitch.
5.7 Arranging lengths of objects
Activity 5.7.1
Activity 5.7.2
5.8 Addition of lengths
Activity 5.8
5.9 Subtraction of units of lengths
Activity 5.9
5.10 Multiplication of units of length per a whole number
Activity 5. 10
5.11 Division of length by a whole number
Activity 5. 11
5.12 Word problems involving units of length
Activity 5. 12
Study this example on the word problem:
Example:
The distance between our classroom and the office of Headteacher is 45 dm. The distance between the office and
the play ground is 55dm. Find the total distance in meters between our classroom and the playground.
Solution:
Distance between our classroom and the office of Headteacher: 45 dm
Distance between the office and the play ground : 55 dm
The distance between our classroom and the play ground is 10 m.
Solve problems:
1. Last year I planted a tree with 50 dm of height. Today, the tree has 80dm.
What is the difference in the height of this tree?
2. A carpenter bought a piece of timber measuring 100cm. He cut it into 5 equal parts. How long is each part?
3. Gatari bought a rope of 60 m. He wants to cut it in 3 equal ropes. What would be the length of each part.
4. Gatera had a field of 89m of length. Munezero’s field had 97 m of length.
(a) Between them, who had a longer field?
(b) Find the difference between their fields?
5. The distance from our home to school is 420 dm. Convert this distance in m.
5.13 The uses of units of length
Activity 5.13.1
Note:
Activity 5.13.2
Activity 5.13.3
5. 14 END UNIT ASSESSMENT 5
1. Comment by Yes or No
(a) The length for my class table is 100 cm ….....…...
(b) The meter is the standard unit of length measurement….........................
(c) We use the tape meter to measure the length of a cloth. ……………………….
(d) Units of length help us to find the measurement of length for objects………………..
(e) I use a meter ruler to measure the length for my notebook. ……………………..
(f) The units of length vary from one the next in the multiple of ten…………………..
2 Use a conversion table to convert
3. Use <, > or = to compare lengths
4. Arrange the lengths for objects from the shortest to the longest: 9 m, 75 dm, 8 m, 85 dm.
5. Arrange the lengths for objects from the longest to the shortest: 756 cm, 87 dm, 967 cm, 68 dm.
6.Work out:
7.Word problems
(a) Gisa walks on foot to go to visit his friend. He covers a distance of 45m. Convert this distance in dm.
(b) Keza bought a long cloth of 79m. She sold 70 dm from it. How long is the remaing piece of cloth cloth?
(c) Mucuruzi bought a cloth of 75m. He divided it in 5 equal parts. Find the length for each part.
(d) During the running race, the competitor Gwiza made 100m in 6 consecutive periods.
Find the total length covered by Gwiza.