The mean of 10 observations is 15 3 If two observations 6 and 9 are replaced by 8 and - Maths -

Question

The mean of 10 observations is 15 3 If two observations 6 and 9
are replaced by 8 and 14 respectively Find the new mean

Pronay · Accepted Answer

Let sum of unchanged 8 numbers is S

then

$\frac{S+6+9}{10} = 15.3$

New mean is equal to

$\frac{S+8+14}{10} = \frac{S+15+7}{10} = \frac{S+15}{10} + \frac{7}{10} = 15.3 + \frac{7}{10} = \frac{153 + 7}{10} = 16$

The mean of 10 observations is 15.3. If two observations 6 and 9 are replaced by 8 and 14 respectively. Find the new mean.