find the sum of first 30 terms of ap 7,12,17,22.....ans is 2385
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Step-by-step explanation:
n=30
AP is 7,12,17,22......
Therefore, a=7
d=a2-a=12-7 = 5
An= a+(n-1)d
A30= 7+(30-1)5 =7+145 =152
By sum formula
Sn=n/2( a+An)
S30=30/2(7+152)
=15*159
=2385
Solved!
Hope it helps you.
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