G8_SiddarthaNagar_8_2081


  1. Two sets are given: \(A = \{1, 2, 3\}\) and \(B = \{2, 3, 4\}\).
    1. Are sets \(A\) and \(B\) disjoint sets? Give a reason.[1]
    2. Write the improper subsets of set \(A\).[1]
    3. Write the proper subsets formed from set \(B\).[1]
    1. No, sets \(A\) and \(B\) are not disjoint sets.
      Because they have common elements \(2\) and \(3\), i.e., \(A \cap B = \{2, 3\} \neq \emptyset\).
    2. The improper subsets of set \(A\) is
      \(\{1, 2, 3\}\) (the set itself)
    3. The proper subsets of set \(B = \{2, 3, 4\}\) are all subsets except \(B\) itself. They are
      \(\{2\}, \{3\}, \{4\}, \{2, 3\}, \{2, 4\}, \{3, 4\}, \emptyset\)
      Number of Elements Subsets Count
      0 \(\emptyset\) 1
      1 \(\{2\}, \{3\}, \{4\}\) 3
      2 \(\{2, 3\}, \{2, 4\}, \{3, 4\}\) 3
      Total Proper Subsets 7
  2. The distance between Bhairahawa and Kathmandu is 275000 m.
    1. Write the distance in scientific notation.[1]
    2. Convert 1050 into the quinary number system.[2]
    3. The distance between Bhairahawa and Nepalgunj is 255000 m. Find the ratio of the distances between the two pairs of cities.[2]
  3. Pranavi bought a mobile phone of marked price Rs 12000 at a \(20\%\) discount.
    1. Write the formula to calculate the discount amount if the discount rate is \(D\%\) and the marked price is MP.[1]
    2. Find the discount amount on the mobile phone.[1]
    3. Find the selling price of the mobile phone.[1]
    4. If the mobile phone is sold at a \(4\%\) loss, find the cost price.[1]
    1. Formula to calculate the discount amount is
      Discount Amount = \( \dfrac{D}{100} \times \text{MP} \)
    2. Finding the discount amount
      Marked Price (MP) = Rs. \(12,000\)
      Discount Rate = \(20\%\)
      Therefore,
      Discount = \( \dfrac{20}{100} \times 12,000 = 2,400 \)
      So, the discount amount is Rs. \(2,400\).
    3. Finding the selling price (SP)
      SP = MP – Discount = \(12,000 - 2,400 = 9,600\)
      So, the selling price of the mobile phone is Rs. \(9,600\).
    4. Finding the cost price (CP) when sold at a \(10\%\) loss
      Selling Price (SP) = Rs. \(9,600\)
      Loss = \(4\%\)
      Thus,
      \( SP= 96 \% \times \text{CP} \)
      or\( 9600 = \dfrac{96}{100} \times \text{CP} \)
      or\( \text{CP} = \dfrac{9600 \times 100}{96} =10000 \)
      So, the cost price of the mobile phone was Rs. \(10,000\).
  4. Anita deposited Rs 3,50,000 in a bank at the rate of 12% per annum for 2 years.
    1. Write the formula to calculate the amount.[1]
    2. How much interest does Anita get in 2 years?[2]
    3. 18 men can complete a work in 30 days. How many men can finish the same work in 36 days?[2]
    1. Formula to calculate amount:
      Amount (A) = Principal (P) + Interest (I)
      or,
      Amount (A) = \( P \left( 1 + \dfrac{T \times R}{100} \right) \)
    2. Interest for 2 years:
      Principal (P) = Rs. 3,50,000
      Time (T) = 2 years
      Rate (R) = 12%
      Thus,
      Interest (I) = \( \dfrac{P \times T \times R}{100} = \dfrac{3,50,000 \times 2 \times 12}{100} = 84,000 \)
      So, Anita gets Rs. 84,000 interest.
    3. Work and Men calculation:
      To finish work in 30 days, men required = 18
      To finish work in 1 day, men required = \( 18 \times 30 \)
      Thus,
      To finish work in 36 days, men required = \( \dfrac{18 \times 30}{36} = 15 \)
      So, 15 men can finish the work in 36 days.
  5. Manisha has a plot of land in the shape of a parallelogram. She wishes to construct a circular pond of radius 14 m inside it. The base of the parallelogram is 150 m and the height is 18 m.
    1. Write the formula to calculate the area of a parallelogram and a circle. [1]
    2. Find the area of Manisha's plot. [1]
    3. What is the area of the plot excluding the pond? [2]
    4. How many meters of wire netting are needed to fence around the pond? [1]
    1. Area formulas
      We know that,
      Area of parallelogram (\( A \)) = base (\( b \)) \(\times\) height (\( h \))
      Area of circle (\( A \)) = \( \pi r^2 \)
    2. Area of Manisha's plot
      Given that,
      Base (\( b \)) = 150 m
      Height (\( h \)) = 18 m
      Now using the formula, we get
      Area of plot (\( A_{p} \)) = \( 150 \times 18 = \) 2700 m²
    3. Area of the plot excluding the pond
      We know that,
      Radius of pond (\( r \)) = 14 m
      Calculating the area of the circular pond,
      Area of pond (\( A_{c} \)) = \( \pi r^2 = \frac{22}{7} \times 14^2 = 616 \) m²
      Therefore,
      Area excluding pond = \( A_{p} - A_{c} = 2700 - 616 = \) 2084 m²
    4. Wire netting needed for the pond
      We know that,
      Circumference (\( C \)) = \( 2\pi r \)
      According to the question,
      Wire needed = \( 2 \times \frac{22}{7} \times 14 = \) 88 m
    1. Find the H.C.F. of: \(3x^{2} - 27\) and \(2x - 6\).[2]
    2. Simplify: \(\dfrac{x^{2}}{x + y} - \dfrac{y^{2}}{x + y}\)[2]
    1. What is the value of \((9 + x)^{0}\)? Write it.[1]
    2. At what value(s) of \(x\) is the expression \(x^{2} - 3x + 2\) equal to zero?[2]
  6. Two equations are given: \(x + y = 6\) and \(x - y = 2\).
    1. What are these equations called?[1]
    2. Solve the given equations using the graphical method.[2]
  7. In the given figure, lines \(KL\) and \(MN\) are intersected by transversal \(DE\) at points \(A\) and \(C\) respectively. \(\angle KAC = 60^{\circ}\).
    1. Write one pair of alternate angles.[1]
    2. Find the value of \(x\).[2]
    3. Verify experimentally that the base angles of an isosceles triangle are equal. (Two figures of different sizes are required.)[3]
    1. Find the coordinates of the image of the line segment joining \(P(5, 3)\) and \(Q(1, 6)\) after reflection in the \(y\)-axis.[1]
    2. Find the distance between points \(P\) and \(Q\).[2]
    3. The bearing of \(P\) from \(Q\) is \(060^{\circ}\). Find the bearing of \(Q\) from \(P\).[1]
    1. Construct a rectangle \(ABCD\) with \(AB = 5cm\) and \(BC = 4cm\).[3]
    2. In the given figure, \(\angle RPQ = \angle ABC\), \(PR = BC\), and \(PQ = AB\). Prove that \(\triangle PQR \cong \triangle ABC\).[2]
  8. The marks obtained by a Grade VIII student (out of \(50\)) in four subjects are given below:
  9. Subject English Mathematics Science Social Studies
    Obtained Marks \(45\) \(30\) \(42\) \(30\)
    1. Find the mode of the given data.[1]
    2. Represent the given data in a pie chart.[2]

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