1. Total sum of money = ₹3000 Let the number of winners of ₹100 be x. And those who are not winners = 63-x According to the question, 100Xx+25X(63-x)=3000 ⇒ 100x+1575-25x=3000 ⇒ 75x+1575=3000 ⇒ 7x+1575-1575=3000-1575 [Subtracting 1575 from both sides] ⇒ 7x-1425 ⇒ 7x/7=1425/7 [Dividing both sides by 7]Read more

    Total sum of money = ₹3000
    Let the number of winners of ₹100 be x.
    And those who are not winners = 63-x
    According to the question, 100Xx+25X(63-x)=3000
    ⇒ 100x+1575-25x=3000
    ⇒ 75x+1575=3000
    ⇒ 7x+1575-1575=3000-1575 [Subtracting 1575 from both sides]
    ⇒ 7x-1425
    ⇒ 7x/7=1425/7 [Dividing both sides by 7]
    ⇒ x=19

    Hence the number of winner is 19.

    Class 8 Maths Chapter 2 Exercise 2.2 Solution in Video

    for more answers vist to:
    https://www.tiwariacademy.com/ncert-solutions/class-8/maths/chapter-2/

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  2. Total sum of money = ₹300 Let the number of ₹5 coins be x, number of ₹2 coins be 3x and number of ₹1 coins be 160-(x+3x)=160-4x According to question, 5Xx+2X(3x)+1X(160-4x)=300 ⇒ 5x+6x+160-4x=300 ⇒ 7x+160=300 ⇒ 7x+160-160=300-160 [Subtracting 160 from both sides] ⇒ 7x-140 ⇒ 7x/7=140/7 [Dividing bothRead more

    Total sum of money = ₹300
    Let the number of ₹5 coins be x, number of ₹2 coins be 3x and number of ₹1 coins
    be 160-(x+3x)=160-4x
    According to question, 5Xx+2X(3x)+1X(160-4x)=300
    ⇒ 5x+6x+160-4x=300
    ⇒ 7x+160=300
    ⇒ 7x+160-160=300-160 [Subtracting 160 from both sides]
    ⇒ 7x-140
    ⇒ 7x/7=140/7 [Dividing both sides by 7]
    ⇒ x=20

    Hence, the number of coins of ₹5 denomination = 20
    Number of coins of ₹2 denomination = 3 x 20 = 60
    Number of coins of ₹1 denomination = 160 – 4 x 20 = 160 – 80 = 80

    Class 8 Maths Chapter 2 Exercise 2.2 Solution in Video

    for more answers vist to:
    https://www.tiwariacademy.com/ncert-solutions/class-8/maths/chapter-2/

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  3. Let number of notes be 2x,3x and 5x. According to question, 100x2x+50x3x+10x5x=4,00,000 ⇒ 200x+150x+50x=4,00,000 ⇒ 400x-4,00,000 ⇒ 400x/400=4,00,000/400 [Dividing both sides by 400] ⇒ x=1000 Hence, number of denominations of ₹100 notes = 2 x 1000 = 2000 Number of denominations of ₹50 notes = 3 x 100Read more

    Let number of notes be 2x,3x and 5x.
    According to question, 100x2x+50x3x+10x5x=4,00,000
    ⇒ 200x+150x+50x=4,00,000
    ⇒ 400x-4,00,000
    ⇒ 400x/400=4,00,000/400 [Dividing both sides by 400]
    ⇒ x=1000
    Hence, number of denominations of ₹100 notes = 2 x 1000 = 2000
    Number of denominations of ₹50 notes = 3 x 1000 = 3000
    Number of denominations of ₹10 notes = 5 x 1000 = 5000
    Therefore, required denominations of notes of ₹100, ₹50 and ₹10 are 2000, 3000 and
    5000 respectively.

    Class 8 Maths Chapter 2 Exercise 2.2 Solution in Video

    for more answers vist to:
    https://www.tiwariacademy.com/ncert-solutions/class-8/maths/chapter-2/

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  4. Let the rational number be x. According to the question, 5/2x+2/3=-7/12 ⇒ 5/2 x+2/3-2/3=-7/12-2/3 [Subtracting 2/3 from both sides] ⇒ 5x/2=-7-8/12 ⇒ 5x/2=-15/12 ⇒ 5xX12=-15x2 ⇒ 60x=-30 ⇒ 60x/60=-30/60 [Dividing both sides by 60] ⇒ x=-1/2 Hence, the rational number is -1/2 for more answers vist to: hRead more

    Let the rational number be x.
    According to the question, 5/2x+2/3=-7/12
    ⇒ 5/2 x+2/3-2/3=-7/12-2/3 [Subtracting 2/3 from both sides]
    ⇒ 5x/2=-7-8/12 ⇒ 5x/2=-15/12
    ⇒ 5xX12=-15×2 ⇒ 60x=-30
    ⇒ 60x/60=-30/60 [Dividing both sides by 60]
    ⇒ x=-1/2
    Hence, the rational number is -1/2

    for more answers vist to:
    https://www.tiwariacademy.com/ncert-solutions/class-8/maths/chapter-2/

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  5. Let Ravi’s present age be x years. After fifteen years, Ravi’s age = 4x years. Fifteen years from now, Ravi’s age = (x+15) years. According to question, 4x=x+15 ⇒ 4x-x=15 [Transposing x to L.H.S.] ⇒ 3x=15 ⇒ 3x/3=15/3 [Dividing both sides by 3] ⇒ x=5 years Hence, Ravi’s present age be 5 years. for moRead more

    Let Ravi’s present age be x years. After fifteen years, Ravi’s age = 4x years.
    Fifteen years from now, Ravi’s age = (x+15) years.
    According to question, 4x=x+15
    ⇒ 4x-x=15 [Transposing x to L.H.S.]
    ⇒ 3x=15
    ⇒ 3x/3=15/3 [Dividing both sides by 3]
    ⇒ x=5 years

    Hence, Ravi’s present age be 5 years.

    for more answers vist to:
    https://www.tiwariacademy.com/ncert-solutions/class-8/maths/chapter-2/

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