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Final review: what we learned this year
Textbook: Part 4, pp. 74–75
GoalReview of the whole year: perimeter, area, volume, multiplication and division, place values.
New words
perimeter · perimetrarea · yuzvolume · hajmequation · tenglama
Explanation
We recall what we learned this year. Perimeter is the sum of the side lengths. Area of a rectangle = length × width; volume is measured in cm³, and the volume of a cuboid = length × width × height. If the area is 310 cm² and the length 31 cm, the width is 310 : 31 = 10 cm. 1 km = 1000 m. The number 908 has no tens. A cube has 6 faces, and a disc is a flat shape.
Worked examples
A rectangle 25 cm by 5 cm has area 25 × 5 = 125 cm².
If the area is 400 cm² and the width is 10 cm, the length is 400 : 10 = 40 cm.
Class activity
“Year quiz”: 10 question cards (formula, unit, shape, calculation). Each has answer options A, B, D. Teams hold up an answer card and collect points.
Practice
1
76 × 3 = ?
228
2
800 : 40 = ?
20
3
A rectangle has sides 25 cm and 5 cm. What is its area in cm²?
125
4
A rectangle has area 310 cm² and length 31 cm. What is its width in centimetres?
10
5
A rectangle has area 400 cm² and width 10 cm. What is its length in centimetres?
40
6
x × 7 = 77, x = ?
11