G8_Birendranagar Surkhet_8_2081


  1. Observe the given Venn diagram and answer the following questions.
    1. Write the common elements of sets \(A\) and \(B\).[1]
    2. Write a proper subset of set \(A\).[1]
    3. If \(t\) is removed from set \(B\), then write the relation of sets \(A\) and \(B\) in set notation.[1]
    1. The common elements of sets \(A\) and \(B\) are those in the intersection region, whihch is
      \( A \cap B = \{r, s\} \)
    2. From the Venn diagram, \(A = \{p, q, r, s\}\).
      One proper subset of \(A\) is \(\{p, q\}\)
      Number of Elements Proper Subsets (examples) Count
      0 \(\emptyset\) 1
      1 \(\{p\}, \{q\}, \{r\}, \{s\}\) 4
      2 \(\{p,q\}, \{p,r\}, \{p,s\}, \{q,r\}, \{q,s\}, \{r,s\}\) 6
      3 \(\{p,q,r\}, \{p,q,s\}, \{p,r,s\}, \{q,r,s\}\) 4
      Total Proper Subsets 15
    3. If \(t\) is removed, then new set \(B = \{r, s\}\)
      Then the relation of sets \(A\) and \(B\) in set notation is \( B \subset A \).
  2. Ram obtained \(45\) marks in math subject of class \(8\) exam.
    1. Write it in scientific notation.[1]
    2. Convert it into binary number system.[2]
    3. Convert \(0.\overline{35}\) into a fraction.[1]
  3. A shopkeeper marked the price Rs 60000 for a computer and sold it with \(10\%\) discount.
    1. If marked price and discount percent are denoted by \(MP\) and \(D\%\) respectively, write the formula to find the discount amount.[1]
    2. What will be the discount amount if \(10\%\) discount is given?[1]
    3. Selling after \(10\%\) discount, it becomes a profit of Rs 4000. Find the cost price.[2]
    1. Formula to find the discount amount:
      Discount Amount = \( \dfrac{D}{100} \times MP \)
    2. Discount amount
      Marked Price (MP) = Rs. 60,000
      Discount = \(10\%\)
      Thus
      Discount Amount = \( \dfrac{10}{100} \times 60,000 = 6,000 \)
      So, the discount amount is Rs. \(6,000\).
    3. Cost price
      Marked Price (MP) = Rs. 60,000
      Discount = \(10\%\)
      Thus
      Selling Price (SP) = 90% of MP = \( \dfrac{90}{100} \times 60,000 = 54,000 \)
      Profit = Rs. 4,000
      We know
      CP =SP-profit= \(54,000 - 4,000 = 50,000\)
      So, the cost price was Rs. 50,000.
  4. Roshani deposited Rs 40,000 in a bank to gain interest at the rate of 10% per annum for 18 months.
    1. Write the formula to find interest.[1]
    2. How much interest will she gain?[2]
    3. How much amount has to be returned to her by the bank?[1]
    4. If Roshani divides the interest she got to Manisha and Anushka in the ratio 2:3, how much money does each get?[2]
    1. Formula to find interest:
      Interest (I) = \( \dfrac{P \times T \times R}{100} \)
    2. Interest gained:
      Principal (P) = Rs. 40,000
      Rate (R) = 10%
      Time (T) = 18 months = \( \dfrac{18}{12} \) years = 1.5 years
      Thus,
      Interest (I) = \( \dfrac{40,000 \times 1.5 \times 10}{100} = 6,000 \)
      So, she will gain Rs. 6,000 as interest.
    3. Total amount to be returned (Amount):
      Principal (P) = Rs. 40,000
      Interest (I) = Rs. 6,000
      Thus,
      Amount (A) = P + I = 40,000 + 6,000 = 46,000
      So, the bank has to return Rs. 46,000 to her.
    4. Money received by Manisha and Anushka:
      Total Interest = Rs. 6,000
      Ratio = 2:3
      Sum of ratios = 2 + 3 = 5
      Thus,
      Manisha's share = \( \dfrac{2}{5} \times 6,000 = 2,400 \)
      Anushka's share = \( \dfrac{3}{5} \times 6,000 = 3,600 \)
      So, Manisha gets Rs. 2,400 and Anushka gets Rs. 3,600.
  5. The given figure is a rectangular-shaped land belonging to Susma, and there is a swimming pool having 14 m diameter inside it. The length and breadth of the land are 100 m and 60 m respectively.
    1. Write the formula to find the area of a rectangle. [1]
    2. Find the area of the land. [1]
    3. Find the area of the land excluding the swimming pool. [2]
    4. Is a 90 m long wire enough to fence the swimming pool with 2 rounds of wire? Give a reason. [2]
    1. Area of rectangle formula
      We know that,
      Area (\( A \)) = Length (\( l \)) \(\times\) Breadth (\( b \))
    2. Area of the land
      Given: Length (\( l \)) = 100 m, Breadth (\( b \)) = 60 m
      Area of land (\( A_l \)) = \( 100 \times 60 = 6000 \) m²
    3. Area excluding the swimming pool
      The diameter (\( d \)) of pool = 14 m, so Radius (\( r \)) = 7 m.
      Area of pool (\( A_p \)) = \( \pi r^2 = \frac{22}{7} \times 7^2 = 154 \) m²
      Remaining Area = Area of land - Area of pool
      \( = 6000 - 154 = 5846 \) m²
    4. Wire adequacy check
      Circumference of pool (\( C \)) = \( \pi d = \frac{22}{7} \times 14 = 44 \) m
      Length of wire required for 2 rounds = \( 2 \times 44 = 88 \) m
      Reason: Yes, a 90 m wire is enough because the required length (88 m) is less than the available length (90 m).
    1. Evaluate: \((5a + x)^0\).[1]
    2. Simplify: \(\dfrac{x^2 + 2xy + y^2}{x^2 - y^2} \times \dfrac{x - y}{x + y}\).[2]
  6. Two algebraic expressions are given: \(3x^2 - 12\) and \(x^2 - 8x + 12\).
    1. Find the H.C.F. of the given expressions.[2]
    2. For what value of \(x\) does the expression \(3x^2 - 12\) become zero?[2]
  7. Two equations are given below: \(x + y = 6\) and \(x - y = 1\).
    1. Solve by using a graph.[2]
    2. What is this system of equations called?[1]
  8. In the adjoining figure, \(AB \parallel CD\).
    1. Write the name of a pair of corresponding angles.[1]
    2. Find the value of \(a\).[2]
    3. If the value of \(c\) is not \(50^\circ\), what is the relation of lines \(AB\) and \(CD\)? Write it.[1]
  9. \(\triangle ABC\) and \(\triangle PQR\) are two triangles.
    1. By which axiom are the given triangles congruent? Write it. Also write the name of a pair of corresponding angles.[2]
    2. Construct a rectangle \(PQRS\) with sides \(PQ = 8cm\) and \(QR = 5cm\).[3]
    3. What type of tessellation is given in the figure?[1]
    1. If \(A(-2,3)\), \(B(3,5)\), and \(C(6,1)\) are vertices of \(\triangle ABC\), write down the coordinates of the image of \(\triangle ABC\) after reflecting on the \(x\)-axis and sketch both figures on graph paper.[3]
    2. In the given figure, the bearing of point \(Q\) from point \(P\) is \(45^\circ\). Find the bearing of point \(P\) from \(Q\).[2]
  10. The marks secured by a student are given in the table below:
  11. Subject Nepali Math Science English
    Marks \(70\) \(40\) \(50\) \(40\)
    1. Find the mode from the above data.[1]
    2. Present it in a pie chart.[2]

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