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JEE Main202125 Jul 2021Morning ShiftMathematicsStatisticsActual

Consider the following frequency distribution : class 10 - 20 20 - 30 30 - 40 40 - 50 50 - 60 Frequency α 110 54 30 β If the sum of all frequencies is 584 and median is 45 , then | α - β | is equal to .

Correct answer

0

Step-by-step solution

∵ Sum of frequencies = 584 α + 110 + 54 + 30 + β = 584 ⇒ α + β = 390       . . . 1 Now, Median is at 584 2 = 292 th term ∵ Median = 45 (lies in class 40 - 50 ) ⇒ α + 110 + 54 + 15 = 292 ⇒ α = 113       . . . 2 On solving, equations 1 and 2 , we get ⇒ α = 113   &   β = 390 - 113 = 277 ⇒ | α - β | = 164

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