Let's first find the total age of the 7 pupils who left:
7 x 12 = 84
And the total age of the 25 pupils who remained:
25 x 14 = 350
So the total age of all the pupils before the new ones arrived was:
84 + 350 = 434
Now let's add the age of the 6 new pupils:
6 x 11 = 66
The total age of all the pupils after the new ones arrived is:
434 + 66 = 500
And finally, the average age of all the pupils in the class is:
500 / 31 = 16.13 (rounded to two decimal places)
Therefore, the average age of the pupils in the class is 16.13 years.
7 pupils of average age 12 years leave a class of 25 pupils of average age 14 years . If 6 new pupils of average age 11 years join the class, what is the average age of the pupils in the class?
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