PAF Chapter Prep Section Mathematics Class 8 Worksheets for Intervention Classes

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1 The City School PAF Chapter Prep Section Mathematics Class 8 Worksheets for Intervention Classes

2 Task#1 Q1 Given a function, Find the values of y when Q2 Find the gradient of the following linear functions Q3) Find the gradient of the straight line determined by each of the following pair of points: a) The City School /PAF Chapter / Prep Section / Worksheet for Intervention Class / Math /Class 8 Page 2 of 27

3 Task#2 Q1 Write down the co-ordinates of the points of intersections of the graphs of the following equation with y-axis Q2 Find the y intercepts Q3 Given the linear function, Calculate the value of y when The City School /PAF Chapter / Prep Section / Worksheet for Intervention Class / Math /Class 8 Page 3 of 27

4 Task#3 Q1 Find the co ordinates of the point at which the given lines cuts the y-axis Q2 Find any 4 points also find the gradient that satisfy the linear function, calculate and display these points in a table, Q3 Write down the co-ordinates of 4 points of each of the following lines The City School /PAF Chapter / Prep Section / Worksheet for Intervention Class / Math /Class 8 Page 4 of 27

5 Task # 4 Q1 Thirty students were asked how many foreign countries they had visited. The answers are given below a) Construct a frequency table of the above result. b) Represent the frequency distribution using a histogram. c) Find the percentage of pupil who visited 1 country. The City School /PAF Chapter / Prep Section / Worksheet for Intervention Class / Math /Class 8 Page 5 of 27

6 Task # 5 Q1 The marks out of ten scored by a class in a test are as given in the following table. Marks No. of students a) How many students sat for the test? b) Calculate the mean, median and modal marks. c) Find the percentage of students who scored more than the median marks. The City School /PAF Chapter / Prep Section / Worksheet for Intervention Class / Math /Class 8 Page 6 of 27

7 Task # 6 Q1 Find the mean, median and mode of the following set of numbers. a) 1.8, 1.9, 2.0, 1.7, 1.8, 1.9, 1.6, 2.0, 1.8, 1.9, 1.8 b) 12, 18, 24, 20, 18, 11, 20, 29, 41, 20 The City School /PAF Chapter / Prep Section / Worksheet for Intervention Class / Math /Class 8 Page 7 of 27

8 Task # 7 Q1 The table below shows the number of fillings a class of 40 students had at the time of a dental inspection. No. of fillings No. of students Find the mean, median and mode of the given distribution. The City School /PAF Chapter / Prep Section / Worksheet for Intervention Class / Math /Class 8 Page 8 of 27

9 TASK # 8 Q1) Factorize each if the following. Where there are no factors, state so The City School /PAF Chapter / Prep Section / Worksheet for Intervention Class / Math /Class 8 Page 9 of 27

10 TASK # 9 Q1) Use algebraic identities to evaluate the following The City School /PAF Chapter / Prep Section / Worksheet for Intervention Class / Math /Class 8 Page 10 of 27

11 Practice Questions Q1 Simplify each of the following. t) v) Q2 Expand: Q3 Factorize: Q4 Use Algebraic identities to evaluate the following: The City School /PAF Chapter / Prep Section / Worksheet for Intervention Class / Math /Class 8 Page 11 of 27

12 Q5. Find two consecutive positive odd numbers which are such that the square of their sum exceeds the sum of their square by 126. Q6. The area of a rectangular field is and the difference between the lengths of the two adjacent sides is 7m. Find the length of the shorter side and the perimeter of the rectangle. Q7. Given that x =3 is one solution of the equation, calculate the the value of p and hence find the other solution. Q8. The product of two numbers is 154. If the difference between the two numbers is 3, find the numbers. Q9. The sum of a number and twice its square is 36. Find the number. Q10. The sum of the squares of two consecutive even integers is 340.find the two numbers. Q11. The sum of the squares of three consecutive positive numbers is 245. Find the largest number. Q12. Fatimah is 5 years older than Dollah. If the product of their ages is 234, how old is Dollah. Q13.5x articles cost dollars while 2x similar articles cost dollars. Find x. Q14. The length and the width of a rectangle are cm and cm respectively. If the area of the rectangle is 209 cm 2, find a) the value of. b)the perimeter of the rectangle. Q15. When x 2 is divided by the quotient is 12 and the remainder is 1. Find the possible values of x. Q16. The sides of a rectangle are of lengths and. The area of the rectangle is Find x and the perimeter of the rectangle. Q17. If and, calculate the value of. Q18. Factorize. Hence evaluate the value of. Q19. If and, find the value of. Q20. If and, calculate the value of a), b). Q21. Evaluate the following by using algebraic method. a) b). The City School /PAF Chapter / Prep Section / Worksheet for Intervention Class / Math /Class 8 Page 12 of 27

13 Q22. The marks out of ten scored by a class in a test are given in the following table: Q23) The contents of 114 boxes of screws are examined. The diagram shows a histogram for the number of defective screws in each box. a) How many boxes contain no defective screw? b) What is the most common number of defective screw per box? c) How many boxes contain at least 2 defective screws? d) Calculate the fraction of boxes containing less than 4 defective screws per box. Q24) At a telephone exchange, the number of calls received in a minute interval was recorded for ach of one hundred chosen intervals. The results are illustrated by the histogram. a) What is the most common number of calls per interval? b) In how many intervals were 2 calls received per minute? c) What fraction of the intervals chosen were there more than 3 calls per minute? d) What percentage of the interval were there not more than 2 per minute? Q25) Each pupil in a class of 40 pupils was asked to measure the length of the pencil he was using. The results are shown in the histogram. a) What is the shortest length? How many pupils are using pencils of this length? b) What is the most common length? c) What fraction of the class is using pencils of at least 11 cm long? d) Find the percentage of pupils using pencils shorter than 10 cm. The City School /PAF Chapter / Prep Section / Worksheet for Intervention Class / Math /Class 8 Page 13 of 27

14 Q26) A record was kept of the number of packets of potato chips sold each day in a store and the results are as follows: No. of packets No. of days a) On how many days was a record kept of the number of packets of chips sold? b) Calculate the mean number of packets sold. c) Find the difference between the mode and the median. Q27) The table below shows the number of errors made by Peter in typing a report. No. of errors No. of pages a) How many pages are there in Peters report? b) What was the percentage of pages with less than 3 errors? c) What was the mode of the distribution? d) Calculate the mean number of errors made by Peter. Q28) In a Mathematics test, the mean score of 30 students was Mary, one of the 30 students, scored 8 marks. It later transpired that her score was recorded wrongly. After correcting Mary s score the new mean score of the students became what was Mary s actual score? Q29) The following are the heights (in meters) of a group of basket ball players: 1.8, 1.9, 2.0, 1.7, 1.8, 1.9, 1.6, 2.0, 1.8, a) Find i. The model height of the group ii. The median height of the group iii. The mean height of the group, correct to one decimal place b) When the 12 th member joined the group, the mean height became 1.9 m exactly. What was the height of the 12 th member? Q30) Find the mean, median and mode of the following set of numbers. a) 12, 11, 13, 11, 15, 16 b) 12, 18, 24, 20, 18, 11, 20, 29, 41, 20 c) 14.3, 13.5, 10.5, 12.6, 15.3, 16.4, 12.6, 16.0 d) 10.5, 9.6, 7, 11, 9.4, 8.1, 10.4, 11.7, 8.1, 9.4, 8.1 The City School /PAF Chapter / Prep Section / Worksheet for Intervention Class / Math /Class 8 Page 14 of 27

15 Q31) The mean, the median and the mode of 4 numbers are 54, 56 and 60 respectively. Find the mean of the largest and the smallest numbers. Q32) The table shows the number of fillings a class of 40 pupils had at the time of a dental inspection. No. of fillings No. of pupils a) If the mean number of the fillings per pupil is 3.2, find the values of and. b) If the mode is 4, find the largest possible value of and calculate the mean number of fillings per pupil with taking the largest value. Q33) (a) The median of the set of eight numbers is 4.5. Given that seven of the numbers are 7, 2, 13, 4, 8, 2 and 1. Find the eighth number and write down the mode of the eight numbers. (b) The mean of a set of twelve numbers is 5 and the mean of a different set of eight numbers is. Given that the mean of the combined set of twenty numbers is 8, calculate. Q34) Find the gradient of the straight line determined by each of the following pair of points: a) b) Q35) Solve the following simultaneous equations using the graphical method. a) Q36) Write down the coordinates of the points of intersection of the graphs of the following equations with the Y-axis a) y = -9x b) y = 5x + 3 Q37) Simplify the following: The City School /PAF Chapter / Prep Section / Worksheet for Intervention Class / Math /Class 8 Page 15 of 27

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17 Q38) Solve: The City School /PAF Chapter / Prep Section / Worksheet for Intervention Class / Math /Class 8 Page 17 of 27

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19 Q48. Evaluate: The City School /PAF Chapter / Prep Section / Worksheet for Intervention Class / Math /Class 8 Page 19 of 27

20 Q49. Calculate the value of the unknown in the following figures. The City School /PAF Chapter / Prep Section / Worksheet for Intervention Class / Math /Class 8 Page 20 of 27

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22 FACTS TO REMEMBER FORMULAE Linear Graphs The graph is a drawing which shows the relationship between number of quantities. The co ordinates are always written in ordered pair as not as : Where, m is the co efficient of, c is the constant and co efficient of must be 1. Gradient: The measure of the steepness is called the gradient. The gradient of a straight line is the measure of the ratio of the vertical change to the horizontal change. In an equation, m is called the gradient of the line. intercept: In the equation, c is the y-intercept it s a point where a line cuts the y-axis i.e. in the equation, y-intercept is 0. The co ordinates of the point where the line cuts the y-axis is and are two points of a line and the gradient of the line is or Equation of y axis is. Equation of x axis is. Line of the equation is always parallel to x axis. Line of the equation is always parallel to y axis. If m>0, then the line will pass from 1 st quadrant to 3 rd quadrant. If m<0, then the line will pass from 2 nd quadrant to 4 th quadrant. The solution of simultaneous linear equations is the point of intersection of the two lines on their graph. There is no solution of simultaneous linear equations if their graph drawn are two parallel lines in the same plane. The City School /PAF Chapter / Prep Section / Worksheet for Intervention Class / Math /Class 8 Page 22 of 27

23 Statistics Frequency Table : A set of raw data can be organized and then arranged in an orderly way in the form of a frequency table. Histogram / Bar Graph : A frequency table can be represented graphically by a histogram or Bar graph. The area of each bar is proportional to the frequency it represents. There is no gap between the bars of a histogram UnGrouped Data : Mean = Median : Arrange the data in ascending or descending order. For an odd number of data, Median is the middle value. For an even number of data, Median is the SUM OF TWO MID VALUES / 2 Mode : It is the most occurring value. Grouped Data : Mean = where is the sum and Median : CF is the cumulative frequency 1. If is even then calculate 2. If is odd then calculate The City School /PAF Chapter / Prep Section / Worksheet for Intervention Class / Math /Class 8 Page 23 of 27

24 Now search the calculated answer in the CF column 1) If the exact calculated answer is present in the C.F column, then Sum of the of that place and next place divided by 2 is the median. 2) If the calculated answer is not present in the C.F. column, then choose the nearest but greater value in the C.F. column of that C.F. is the median Mode : of the highest frequency The City School /PAF Chapter / Prep Section / Worksheet for Intervention Class / Math /Class 8 Page 24 of 27

25 ALGEBRA Laws of Indices Where m and n are integers and a 0, b 0. Algebraic Identities The City School /PAF Chapter / Prep Section / Worksheet for Intervention Class / Math /Class 8 Page 25 of 27

26 BREAKING OF THE MIDDLE TERM co efficient of ( is the 1 st term) co efficient of ( is the 2 nd term) constant ( c is the 3 rd term ) Find the product of 1 st and the 3 rd. (a X c) Product is positive and the middle term is also positive. Find two such factors of the product that their sum will be equal to the middle term. Both the factors must have positive signs. Find the product of 1 st and the 3 rd. (a X c) Product is positive and the middle term is also negative. Find two such factors of the product that their sum will be equal to the middle term. Both the factors must have negative signs. Find the product of 1 st and the 3 rd. ( a x -c) Product is negative and the middle term is positive. Find two such factors of the product that their difference is equal to the middle term. Sign of the greater factor is positive and smaller factor is negative. Find the product of 1 st and the 3 rd. (a x -c) Product is negative and the middle term is also negative. Find two such factors of the product that their difference is equal to the middle term. Sign of the greater factor is negative and smaller factor is positive. The City School /PAF Chapter / Prep Section / Worksheet for Intervention Class / Math /Class 8 Page 26 of 27

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