Question

Average weight of a group of 6 girls is 26. If we
replace a girl of weight 30 in the group with
another girl so that new average increases by 5.
Find the weight of new girl





Brainliest questions se ree xD​

Answer 1

Answer:

Total weight = 156 - 30 + x = 126+x

$average \: = \frac{126 + x}{6} \\ \\ 31= \frac{126 + x}{6} \\ \\ 186 = 126 + x \\ \\ x = 60$

Answer 2

Given - Number of girl students and average

Find - Weight of new girl student

Solution - Average = sum of all observations/total number of observations

As per the first case -

Sum of weight = 26 * 6

Sum of weight = 156

As per the second case -

Let the weight of new girl student be x.

Sum of new weight = 156 - 30 + x

Sum of new weight = 126 + x

New average = 26 + 5

New average = 31

Solving for the value of x

31 = (126 + x)/6

31 * 6 = 126 + x

186 - 126 = x

x = 60

Hence, the weight of new girl student is 60.