The outcome of each of 30 items was observed; 10 items gave an outcome 1/2 – d each, 10 items gave outcome 1/2 each and the remaining 10 items gave outcome 1/2 + d each. If the variance of this outcome data is 4/3 then |d| equals:

Statistics and Probability: JEE Main 2019 Mathematics question

JEE Main 2019 · 11 Jan, Morning shift · Q5446

JEE Main 201911 Jan, Morning shiftMathematicsMediumStatistics and Probability258× since 2002

The outcome of each of 30 items was observed; 10 items gave an outcome

{1 \over 2}

– d each, 10 items gave outcome

{1 \over 2}

each and the remaining 10 items gave outcome

{1 \over 2}

+ d each. If the variance of this outcome data is

{4 \over 3}

then |d| equals :