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Grade 7 Mathematics Work Sheet GRADE 7 MATHEMATICS WORK SHEET GRADE 7 MATHEMATICS WORK SHEET AMHARA EDUCATION BUREAU CURRICLUM DEVELOPMENT AND IMPLIMENTATION DIRECTORATE AUGUST, 2020 BAHIR DAR. 0 GRADE 7 MATHEMATICS WORK SHEET UNIT FOUR 4. DATA HANDLING 4.1 Ways of collecting data Note:- How can we collect data: By using a questionnaire By making observations and recording the results By carrying out an experiment From records or data base From the internet Exercise 1. Which one is not correct when we are writing questions for a questionnaire? A. Be clear what we want to find out and what data we need. B. Ask short and simple questions. C. Provide tick boxes with possible answers D. Writing vague questions and questions which may influence the answer. 4.2 Some ways of presenting data Note:- A. Collecting data using Tally marks: Tally mark is one way of presenting data by line segments. Example:- //// represents 5 members of the sample. Example: In a survey, 20 pupils were asked how many of their friends they got last Sunday. Here are the results: 3 2 4 1 4 2 5 5 7 6 4 6 3 4 2 6 4 2 8 5 Number of friends Tally Frequency 1 / 1 2 //// 4 3 // 2 4 //// 5 1 GRADE 7 MATHEMATICS WORK SHEET 5 /// 3 6 /// 3 7 / 1 8 / 1 Total 20 Exercise 2. The age of students in a class were recorded as follows: 13 12 13 14 14 13 14 16 14 13 14 13 14 14 14 15 15 14 15 15 15 14 15 14 13 12 15 15 16 15 16 14 16 16 15 16 15 14 16 16 14 16 13 14 14 15 14 15 16 15 13 14 15 14 14 17 17 16 13 14 Show this information more clearly by drawing a tally chart. Note:- B. Line graphs: The line graph is most commonly used to represent two related facts. To plot a line graph, you can take two lines at right angles to each other. These lines are called the axes of reference. Their intersection is called the origin. The number of units represented by a unit length along an axis is called a scale. A line graph is drawn based on pairs of measurements of two quantities. To plot a line graph the following points are important: A. Draw the horizontal and vertical lines (axes) and label them by using appropriate scale so that it should be enough to represent the data to be used. B. Make a table of data arranged in pairs. The first number of each pair is read from the horizontal scale( axis) and the other number is from the vertical scale(axis). Use these numbers to locate points on the graph. C. connects the points by a straight line or a smooth curve. Exercise 3. Draw a line graph to represent each of the following sets of data. a. The temperature in Bahir Dar at midday during the Second week in July Day Sun Mon Tue Wed Thur Fri Sat Temprature(c)•• 13 12 15 14 13 16 12 2 GRADE 7 MATHEMATICS WORK SHEET Note:- C. Pie Chart: Pie chart is a very common and accurate way of representing data especially useful for showing the relations of one item with another and one item with the whole items. The portion of a circular region enclosed between two radii and part of the circumference (an arc) is called a sector of the circle. The size of the sector is determined by the size of the angle formed by the two radii. Exercise 4. Ato Alemayehu family’s had an income of Birr 12,000 per. In month his family expenditure is; Food – 6000 Travel- 800 Rent- 4000 Entertainment-200 Saving- 1000 Construct a pie chart representing the above information? 5. The following pie chart shows a family budget based on a net income of Birr 2400 per month A. Determine the amount spent on rent B. Determine the amount spent on car payments. C. Determine the amount spent on utilities D. How much more money is spent than saving. 30% rent 25% Saving 8% Utilize 10% Others 12% Car 15% payment Grocery 4.3 The mean, Mode, Median and Range of Data Note:- The mean, Mode, Median and Range The mean of a set of data is the sum of all values divided by the number of values. The Mode of a set of data is the value which occurs most frequently. The Median is the middle value when the data is arranged in order of size from the smallest to the largest or from the largest to the smallest. 3 GRADE 7 MATHEMATICS WORK SHEET The range of a set of data is the difference between the highest value and the lowest value. Exercise 6. What number should be included in the data 2,8,7,4 and 9 so that the mean is 6. A. 7 B. 5 C. 6 D. 8 7. Find the range of data , -5 ,-10, 8, -92 A. 100 B. 87 C. 92 D. 97 8. The middle value in an arrangement of data in a sending or descending order is called? A. Mean B. mode C. median D. Range 9. Which of the following is measure of dispersion ? A. Mode B. Range C. median D. mean 10. What is the mode of the data: 8, 4, 6, 8, 7, 4, 9? A. 6 B. 7 C. 4 and 8 D. 9 UNIT FIVE 5. GEOMETRIC FIGURES AND MEASUREMENT OF QUADRILATERAL Note:- Quadrilateral : Is a four sided geometric figure bounded by line segments? The point at which the sides are connected are vertices. Adjacent sides of a quadrilateral are sides that have a common end point. Opposite sides are sides that have no common points. A diagonal is a line segment that connects two opposite vertices. Note:- A Trapezium : Is a special type of quadrilateral in which exactly one pair of opposite sides are parallel. The parallel sides are called the bases of the trapezium. The distance between the bases is known as the height ( altitude) of the trapezium. Exercise 11. Which of the following is not a special parallelogram? A. Trapezium B. Rectangle C. Rhombus D. Square 12. Diagonals of any quadrilateral are equal. A. True B. False 4 GRADE 7 MATHEMATICS WORK SHEET 13. A polygon having four sides is called---------------------------- A. Pentagon B. Quadrilateral C. Hexagon D. Decagon 14. DEFG is a quadrilateral D A. Name all its vertices E B. Name all its sides G C. Name all pairs of opposite sides F D. Name all pairs of opposite sides E. Name adjacent sides of a quadrilateral. Note:- parallelogram: A parallelogram is a quadrilateral in which each side is parallel to the side opposite to it. Opposite sides of a parallelogram are congruent and parallel. The diagonals of a parallelogram bisect each other Opposite angles of a parallelogram are congruent and consecutive angles of a parallelogram are supplementary. Note:- Special parallelograms: Rectangle , Rhombus and Square are special parallelograms. Exercise 15. Write the properties of A. Rectangle ------------------------------------ B. Rhombus --------------------------------------- C. Square------------------------------------------- 16. A special type of quadrilateral in which exactly one pair of opposite sides are parallel is---- A. Parallelogram B. Rectangle C. Trapezium D. Rhombus 17. ABCD is a parallelogram, if measure of angle A is 110°, then what is measure of angle D? A D A. 110° B. 70° C. 350° D, 250° B C 18. In rectangle ABCD the length of diagonal AC is given by (20× +2) cm and diagonal BD is ( 14× +14) cm. what is the length of AC? A B A. 52 cm B. 32 cm C. 42 cm D. 2cm D C 5 GRADE 7 MATHEMATICS WORK SHEET 19. Find the length of the side of a rhombus whose diagonals are length of 12cm and 16cm. A. 5cm B. 10 cm C. 6 cm D. 8 cm 20. ABCD is a square. Find the measuring < ADB ? A B A. 90° B. 60° C. 45° D. 35° D C Match column A with column B with the appropriate property more than once. A B 21. All diagonals are equal in length A. Rectangle 22. All angles are equal B. Parallelogram 23. All sides are equal C. Rhombus 24. The diagonals bisect the angle at the vertices D. Trapezium 25. The diagonals bisect each other at right angle E. Quadrilateral Note:- POLYGON: Is a simple closed plane figure formed by three or more line segments joined end to end. A. A Convex polygon is a simple polygon in which all of its interior angles measures less than 180° each. B. A Concave polygon is a simple polygon which has at least one interior angle of measures greater than 180° A diagonal of a convex polygon is a line segment whose end points are non- consecutive vertices of the polygon. If the number of sides of a polygon is ‘’n” , then, Number of diagonals drawn from one vertex is n-3. Number of all possible diagonals is n(n-3)/2 Exercise 26. How many possible diagonals are there in a polygon of 8 sides? A. 20 B. 40 C. 35 D. 15 27. A simple polygon which has at least one interior angle of measures greater than 180° is------- A. Convex B. Concave C. Square D. Rectangle 6 GRADE 7 MATHEMATICS WORK SHEET Match column A with column B with the appropriate name and number of sides. A B 28. Hexagon A. 9 sides 29. Quadrilateral B. 5 sides 30. Octagon C. 8 sides 31.
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