Let a1,a2,...,a2024 be an Arithmetic Progression such that a1+(a5+a10+a15+...+a2020)+a2024=2233. Then a1+a2+a3+...+a2024 is equal to __________. [2025]
(11132)
We have,
a1+a5+a10+a15+...+a2020+a2024=2233 ... (i)
Since, a1,a2,...,a2024 be in A.P.
∴ a1+a2024=a5+a2020=a10+a2015.....
{Sum of terms equidistant form ends is equal}
From (i), we get
(a1+a2024)+(a5+a2020)+(a10+a2015)+...=2233
⇒ 203(a1+a2024)=2233 [∵ Total pairs = 203]
⇒ a1+a2024=11
∴ Sum of n terms in A.P. is
Sn=n2(a1+a2024)
=1012×11 [∵ n = 2024]
∴ Sn=11132.