Answer:
1025
Explanation
The formula to find the sum of the first n terms of an arithmetic sequence is
Sn = n/2 * [2a1 + (n-1)d]
Where
a1 = the first term of the sequence
d = the common difference between consecutive terms
n = the number of terms we want to sum
Substituting the given values, we get
a1 = 5
d = 3
n = 25
S25 = 25/2 * [2(5) + (25-1)3]
= 25/2 * [10 + 72]
= 25/2 * 82
= 25 * 41
= 1025