Question

Q.
The average of 73 natural numbers is 219. If the first number is decreased by 4, second by 7, third by 10 and so on, find the average of new set of numbers.​

Answer 1

Answer:

Step-by-step explanation:

average of 73 numbers=219

x/73=219

x=15987

given first number is decreased by 4 and next is by 7 and next by 10

with a common difference of 3

x-(4+7+10+13+-------+73rd term)/73

x-(sum of 73 terms in AP)/73

15987-((73/2(8+(72)*3))/73

=15987-((73/2)(224))/73

=15987-(73*112)/73

=73*219-112*73/73

73(219-112)/73

=107