Question

marks of 12 students in a unit test are given as 4,21,13,17,5,9,10,20,19,12,20,14.assume a mean and calucate the arthematic mean of the data assume another number as mean and caucalate the arthematic mean again do you get the same result ? comment

Answer 1

Answer:

13.66666667

Step-by-step explanation:

4+21+13+17+5+9+10+20+19+12+20+14=164

Arthematic mean =sum of numbers\no.of numbers

164÷12=13.66666667

This is solution of this problem

Answer 2

Step-by-step explanation:

Let assumed mean be 13

∴ Arithmetic mean = 13+

[ (4−13)+(21−13)+(13−13)+(17−13)+(5−13)+(9−13)+

(10−13)+(20−13)+(19−13)+(12−13)+(20−13)+(14−13)]

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12

= 13+8\12. note:bothfraction

=13+0.67. will be in [ ] this

=13.67 bracket.

Now let assumed mean be 14

∴ Arithmetic mean =14+

(4−14)+(21−14)+(13−14)+(17−14)+(5−14)+(9−14)+

(10−14)+(20−14)+(19−14)+(12−14)+(20−14)+(14−14)

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14

=14+[ -4\12]

=13.67

hope it helps