πŸ“’ Too many exams? Don’t know which one suits you best? Book Your Free Expert πŸ‘‰ call Now!

  • google app store apple app store
  • βœ–

      Question

      The values given in which of the following options will

      fill the blanks in the same order in which it is given to make the statement true: Five years hence, the age of β€˜H’ will be 14 years. Present age of β€˜G’ is 5/3 of the present age of β€˜H’. Present ages of β€˜A’, β€˜B’, β€˜C’, β€˜D’, β€˜E’ and β€˜F’ are in the form of β€˜4p’, β€˜5p’, β€˜q’, β€˜2q’, β€˜3r’ and β€˜4r’ years respectively. If the sum of present ages of β€˜A’ and β€˜E’ is ____ years, difference between present ages of β€˜B’ and β€˜D’ is ____ years, and average present age of β€˜C’ and β€˜F’ is ____ years, then average present age of all the given persons is ____ years. I. 34, 8, 15, 15 II. 35, 9, 14, 18 III. 30, 6, 10, 16
      A Both I and III Correct Answer Incorrect Answer
      B Only III Correct Answer Incorrect Answer
      C Only II Correct Answer Incorrect Answer
      D Both I and II Correct Answer Incorrect Answer
      E Both II and III Correct Answer Incorrect Answer

      Solution

      Present age of 'H' = 14 - 5 = 9 years Present age of 'G' = (5/3) X 9 = 15 years Statement I: Let the present age of 'A', 'B', 'C', 'D', 'E' and 'F' be '4p', '5p', 'q', '2q', '3r' and '4r' years respectively. 4p + 3r = 34 -------- (I) 5p - 2q = 8 -------- (II) (q + 4r) Γ· 2 = 15 q + 4r = 30 --------- (III) On solving equation II + 2 X equation III, 5p - 2q + 2 X (q + 4r) = 8 + 2 X 30 Or, 5p - 2q + 2q + 8r = 8 + 60 Or, 5p + 8r = 68 -------- (IV) On solving 5 X equation I - 4 X equation IV, We get, 5 X (4p + 3r) - 4 X (5p + 8r) = 5 X 34 - 4 X 68 Or, 20p + 15r - 20p - 32r = 170 - 272 Or, 17r = 102 Or, 'r' = 6 On putting value of 'r' in equation I, We get, 4p + 3 X 6 = 34 Or, 4p = 16 Or, 'p' = 4 On putting value of 'r' in equation III, We get, q + 4 X 6 = 30 Or, 'q' = 6 Average present age of all the given person= (4p + 5p + q + 2q + 3r + 4r + 15 + 9) Γ· 8 = (9 X 4 + 3 X 6 + 7 X 6 + 24) Γ· 8 = (120/8) = 15 years So, statement I is true. Statement II: Let the present age of 'A', 'B', 'C', 'D', 'E' and 'F' be '4p', '5p', 'q', '2q', '3r' and '4r' years respectively. 4p + 3r = 35 -------- (I) 5p - 2q = 9 -------- (II) (q + 4r) Γ· 2 = 14 q + 4r = 28 --------- (III) On solving equation II + 2 X equation III, 5p - 2q + 2 X (q + 4r) = 9 + 2 X 28 Or, 5p - 2q + 2q + 8r = 9 + 56 Or, 5p + 8r = 65 -------- (IV) On solving 5 X equation I - 4 X equation IV, We get, 5 X (4p + 3r) - 4 X (5p + 8r) = 5 X 35 - 4 X 65 Or, 20p + 15r - 20p - 32r = 175 - 260 Or, 17r = 85 Or, 'r' = 5 On putting value of 'r' in equation I, We get, 4p + 3 X 5 = 35 Or, 4p = 20 Or, 'p' = 5 On putting value of 'r' in equation III, We get, q + 4 X 5 = 28 Or, 'q' = 8 Average present age of all the given person= (4p + 5p + q + 2q + 3r + 4r + 15 + 9) Γ· 8 = (9 X 5 + 3 X 8 + 7 X 5 + 24) Γ· 8 = (128/8) = 16 years So, statement II is false. Statement III: Let the present age of 'A', 'B', 'C', 'D', 'E' and 'F' be '4p', '5p', 'q', '2q', '3r' and '4r' years respectively. 4p + 3r = 30 -------- (I) 5p - 2q = 6 -------- (II) (q + 4r) Γ· 2 = 10 q + 4r = 20 --------- (III) On solving equation II + 2 X equation III, 5p - 2q + 2 X (q + 4r) = 6 + 2 X 20 Or, 5p - 2q + 2q + 8r = 6 + 40 Or, 5p + 8r = 46 -------- (IV) On solving 5 X equation I - 4 X equation IV, We get, 5 X (4p + 3r) - 4 X (5p + 8r) = 5 X 30 - 4 X 46 Or, 20p + 15r - 20p - 32r = 150 - 184 Or, 17r = 34 Or, 'r' = 2 On putting value of 'r' in equation I, We get, 4p + 3 X 2 = 30 Or, 4p = 24 Or, 'p' = 6 On putting value of 'r' in equation III, We get, q + 4 X 2 = 20 Or, 'q' = 12 Average present age of all the given person= (4p + 5p + q + 2q + 3r + 4r + 15 + 9) Γ· 8 = (9 X 6 + 3 X 12 + 7 X 2 + 24) Γ· 8 = (128/8) = 16 years So, statement III is true. Hence, option a.

      Practice Next
      ask-question