Approximation


Direction: What approximate value should come in place of the question mark(?) in the following question ? (Note that you are not expected to calculate the exact value).

  1. (9.95)2 x (2.01)3 = 2 x (?)2
    1. 12
    2. 15
    3. 25
    4. 20

  1. View Hint View Answer Discuss in Forum

    (9.95)2 x (2.01)3 = 2 x (?)2
    Here, 9.95 is Approximated to 10, 2.01 is approximate to 2 because calculating the square or cubes of whole number is much easier than to calculate the square or cube of decimal numbers
    2 x (?) 2 = ( 10)2 x (2)3 = 100 x 8 = 800

    Correct Option: D

    (9.95)2 x (2.01)3 = 2 x (?)2
    Here, 9.95 is Approximated to 10, 2.01 is approximate to 2 because calculating the square or cubes of whole number is much easier than to calculate the square or cube of decimal numbers
    2 x (?) 2 = ( 10)2 x (2)3 = 100 x 8 = 800
    ⇒ (?)2 = 400
    ∴ ? =20


  1. 99.999 ÷ 0.99 ÷ 0.00991234 = ?
    1. 100
    2. 10000
    3. 1000
    4. 100000

  1. View Hint View Answer Discuss in Forum

    99.999 ÷ 0.99 ÷ 0.00991234 = 100 ÷ 1 ÷ 0.01

    Correct Option: B

    99.999 ÷ 0.99 ÷ 0.00991234
    = 100 ÷ 1 ÷ 0.01 = 10000



  1. [137 ÷ 17 x 3.99]/[4.02 x 3.98] = ?
    1. 3.2
    2. 3.5
    3. 2.5
    4. 2

  1. View Hint View Answer Discuss in Forum

    [137 ÷ 17 x 3.99]/[4.02 x 3.98] = ? ≈ (137 ÷ 17 x 4) / (4 x 4)

    Correct Option: D

    [137 ÷ 17 x 3.99]/[4.02 x 3.98] = ? ≈ (137 ÷ 17 x 4) / (4 x 4) ≈ 2


  1. 953.7 ÷ 95 0.9989 = 95?
    1. 1.9
    2. 3
    3. 2.99
    4. 2.7

  1. View Hint View Answer Discuss in Forum

    ? = 953.7 ÷ 950.9989 = 95?
    ⇒ 95(3.7 - 0.9989) = 95?
    ⇒ 952.7011 = 95?

    Correct Option: D

    ? = 953.7 ÷ 950.9989 = 95?
    ⇒ 95(3.7 - 0.9989) = 95?
    ⇒ 952.7011 = 95?
    ∴ ? = 2.7011 ≈ 2.7



  1. 37.5/271.5 x 92 = 3?
    1. 5
    2. 4.5
    3. 7
    4. 6.50

  1. View Hint View Answer Discuss in Forum

    3 7.5 ÷ 271.5 x 92 = 3?
    ⇒ 37.5 ÷ (3)3 x 15 x 32 x 2 = 3 ?

    Correct Option: C

    3 7.5 ÷ 271.5 x 92 = 3?
    ⇒ 37.5 ÷ (3)3 x 15 x 32 x 2 = 3 ?
    ⇒ 37.5 - 4.5 + 4 = 3? ⇒ 37 = 3? ⇒ ? = 7