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99 Percentile Qs Bank for JEE MainMathematicsStatistics

The arithmetic mean of marks in Mathematics for four divisions A, B, C and D were 80, 75, 70 and 72 respectively. Their standard deviations were 12,6,8 and and 10 respectively. Then, division has more uniformity.

Options

  1. AD
  2. BB
  3. CC
  4. DA

Correct answer

B. B

Step-by-step solution

aligned & We know that C.V. = Standard Deviation Mean & ( C.V. )_A= 12 18 =0.15 and ( C.V. )_B= 6 75 =0.08 & ( C.V. )_C= 8 70 =0.11 and ( C.V. )_D= 10 72 =0.14 aligned C.V. is the least for division B.

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