INDIAN SCHOOL MUSCAT MIDDLE SECTION DEPARTMENT OF MATHEMATICS FINAL TERM EXAMINATION CLASS - 8 (ANSWER KEY) SECTION A Qns

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1 SECTION A Qns Ans. Find the HCF of 4x y, 6xy, xy xy. Write the standard form of Write the co-ordinates of the Origin. ( 0, 0 ) 4. The number of digits in the square root of 664 is ( ³ + ³ + ³ ) - x 0 6. Find the lateral surface area of a cube of a side cm. 6cm SECTION B 7. Find the least number by which 70 be multiplied to make it a perfect square x x x5 ( ++) least number to be 9 multiplied is 5 () 8. Find the value of (ax + 9y) (ax + 9y) using suitable identity. (ax + 9y) (ax + 9y) (ax) +.ax.9y +(9y) 4a x + 6axy + 8y 9. The area of a rhombus is 080 m and one of the diagonals is 7m.Find the length of the second diagonal. Area of the rhombus d d 0. 7m ( m ) m 5 7m -m + 6 m 5 7m -m-m -5-6 m - INDIAN SCHOOL MUSCAT MIDDLE SECTION DEPARTMENT OF MATHEMATICS FINAL TERM EXAMINATION CLASS - 8 (ANSWER KEY) Ans M M 080 m 7m d d 080 / 6 d 0m. Find the value of using (5 - - ) 6 - suitable laws of exponents. (5 ) 6 [ 5 ] 6 M Factorise ax ay bx + by ax ay bx + by a( x -y) b( x- y) (a b) (x y) M M

2 SECTION C. Vani is 4 years older than Rani.0 years back Vani s age was five times the age of Rani. Find their present ages RANI x x-0 VANI x+4 x+4-0 x + 4 0yrs back, x + 4 5(x-0) x + 4 5x x 64 x 6 Rani s age 6 Vani s age The area of a Trapezium is 540 m². If the parallel sides are 0m and 4 m long, find the distance between them A h ( a +b ) 540 h ( ) h 540 / 54 h 0 m 5. Find the product of (4m + ) and (4m 5) using suitable identity. (4m + ) (4m 5) (4m)² + (- 5)4m + (-5) 6 m²-6m 5 6. Reshma bought a television set for 4000 including 5% VAT. Find the price before VAT and VAT amount. Price before VAT Price After VAT x 4000 () x x price before VAT VAT amount () ( +) Factorise the expression (x² - 4x ) and divide by (x + ) x² - 4x x² - 7x + x - x(x -7) + (x 7) 8. (x 7) (x + ) Divide by (x+) ans (x-7) 8 5 a Evaluate using laws of exponents 4 6 a a 8 4 a a 8 ( 6) 0 a 4 9. Multiply ( a² + 5ab + b² ) by ( a² b ). () M M M M M M M M a (a b ) + 5ab(a b ) + b (a b ) [ ] a 4 6a b + 5a b 5 ab + a b b 4. [ ] a 4 5a b + 5a b 5ab b 4 [ ] 0. Rishi bought a cooler for 00 and spent 40 for repair and sold it at a profit of

3 5%, Find the value of S.P Total C.P C.P Profit S.P x x 00 S.P Rs The distances thrown by competitors in a Javelin throw event are given as Distance(m) Frequency Draw a histogram for the given data. Marking each value & completing each bar No scale (cut ). Construct a rhombus ABCD, AB 4.9cm and /A Correct line segment AB [] Drawing 80 0 angle at A [ ] Drawing arc to get D [] Getting point C [ ] M M each SECTION D. Find the least number to be added to 95 to make it a perfect square. Find the square root of the number so obtained () () ( ) Least no. to be added is 84 () () () 4. Find the amount and the compound interest on 4,000 for year at 0%annum compounded half yearly. R 0 A P[ + ] 4,000[+ ]² , A 6,940 C.I 6,940-4,000, If numerator is less than the denominator of a rational number and when is subtracted from numerator and denominator both, the rational number obtained is t M M M

4 . Find the rational number Denominator x ; Numerator x x x (x-) x- x x x - x - +6 X 5 The required fraction 5 M +M 6. The total surface area of a cylinder is 440m.Find the volume of the cylinder if the radius of its base is 7m. Total Surface area of a cylinder πr(r + h) 440m 7 7(7+h) (7+h) 440 (7+h) 440 / 44 0 h 0-7 m v πr²h m 7 7. Draw a linear graph to show the relationship between the cost and the quantity of onions using the following data. Weight ( in kg) 4 5 Cost( in ) Marking each point Scale & Completion of the graph 8. Simplify using identity (a + b) (a b) (a+b+a-b)(a+b-a+b) [ ] (a + b)(a + 5b) [ ] a +5ab+ab+5b [ ] a +6ab+5b [ ] 9. Construct a quadrilateral PQRS in which /Q 60⁰, /R 90⁰, QR 5cm, PQ 7cm and RS 6.5cm Constructing 60 0 & 90 0 [+] correct sides [++] Correct labeling [] 0. The monthly sale of computers by a shopkeeper is as shown below. Draw a pie chart to represent the data. Months March April May June No. of computers M M M M M + M M Finding the central angle Drawing correct angles

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