824+a+b=4a+b=82=84+1+1+0+1+9+(a−4)2+(b−4)216=48+a2+b2−8a−8ba2+b2=3232=2abab=16a=4b=4 mode =4 mean deviation =82+1+1+0+1+3+0+0=1 option (1)
Let the mean and the standard deviation of the observation 2,3,3,4,5,7, a, b be 4 and 2 respectively. Then the mean deviation about the mode of these observations is :
Held on 4 Apr 2025 · Verified 6 Jul 2026.
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