find the sum of all integers between 92 and 786 shich are multiples of 9 - Maths - Arithmetic Progressions

Question

find the sum of all integers between 92 and 786 shich are multiples
of 9

Neha Sethi · Accepted Answer

Dear student
The numbers between 92 and 786 which are multiples of 9 are:99,108,117,
,774,783Here a=99,d=9,l=783So, l=a+n-1d783=99+n-1977=nNow Sn=n22a+n-1d=772299+77-19=772×882=33957

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