Number System


  1. Divide 50 into two parts so that the sum of their reciprocals is 1/12.









  1. View Hint View Answer Discuss in Forum

    Here, the first divisor (289) is a multiple of second divisor (17).
    ∴  Required remainder = Remainder obtained on dividing 18 by 17 = 1

    Correct Option: D

    Here, the first divisor (289) is a multiple of second divisor (17).
    ∴  Required remainder = Remainder obtained on dividing 18 by 17 = 1


  1. In a class, there are ‘z’ students. Out of them ‘x’ are boys. What part of the class is composed of girls ?









  1. View Hint View Answer Discuss in Forum

    The no. is of the form (425x + 45) First divisor (425) is multiple of second divisor (17).
    ∴  Required remainder
    = Remainder obtained on dividing 45 by 17 = 11

    Correct Option: B

    The no. is of the form (425x + 45) First divisor (425) is multiple of second divisor (17).
    ∴  Required remainder
    = Remainder obtained on dividing 45 by 17 = 11



  1. The numerator of a fraction is 4 less than its denominator. If the numerator is decreased by 2 and the denominator is increased by 1, then the denominator becomes eight times the numerator. Find the fraction.









  1. View Hint View Answer Discuss in Forum

    LCM of 4, 5 and 6 = 60
    Quotient on dividing 800 by 60 = 13
    Quotient on dividing 400 by 60 = 6
    ∴  Required answer = 13 – 6 = 7
    Method 2 :
    First number greater than 400
    that is divisible by 60 = 420
    Smaller number than 800 that
    is divisible by 60 = 780
    It is an Arithmetic Progression with common difference = 60
    with common difference = 60
    By tn
    = a + (n – 1)d
    780 = 420 + (n – 1) × 60
    ⇒  (n – 1) × 60 = 780 – 420 = 360
    ⇒  (n – 1) = 360 ÷ 60 = 6
    ⇒  n = 6 + 1 = 7

    Correct Option: A

    LCM of 4, 5 and 6 = 60
    Quotient on dividing 800 by 60 = 13
    Quotient on dividing 400 by 60 = 6
    ∴  Required answer = 13 – 6 = 7
    Method 2 :
    First number greater than 400
    that is divisible by 60 = 420
    Smaller number than 800 that
    is divisible by 60 = 780
    It is an Arithmetic Progression with common difference = 60
    with common difference = 60
    By tn
    = a + (n – 1)d
    780 = 420 + (n – 1) × 60
    ⇒  (n – 1) × 60 = 780 – 420 = 360
    ⇒  (n – 1) = 360 ÷ 60 = 6
    ⇒  n = 6 + 1 = 7


  1. A rational number between 3/4 and 3/8 is









  1. View Hint View Answer Discuss in Forum

    31 = 3, 32 = 9,
    33 = 27, 34 = 81
    i.e. the unit’s digit = odd number
    ∴  Hence, both numbers are divisible by 2.

    Correct Option: A

    31 = 3, 32 = 9,
    33 = 27, 34 = 81
    i.e. the unit’s digit = odd number
    ∴  Hence, both numbers are divisible by 2.



  1. A fraction becomes 9/11, if 2 is added to both the numerator and the denominator. If 3 is added to both the numerator and the denominator it becomes 5/6. What is the fraction ?









  1. View Hint View Answer Discuss in Forum

    If the first part be x, then second part = 37 – x.
    ∴  x × 5 + (37 – x) 11 = 227
    ⇒  5x + 407 – 11x = 227
    ⇒  6x = 407 – 227 = 180
    ⇒  x = 30
    ∴  Second part = 7

    Correct Option: D

    If the first part be x, then second part = 37 – x.
    ∴  x × 5 + (37 – x) 11 = 227
    ⇒  5x + 407 – 11x = 227
    ⇒  6x = 407 – 227 = 180
    ⇒  x = 30
    ∴  Second part = 7