find s30 of an AP gives that a10=28 and a20=58.
Answers
Answered by
19
d = a20-a10/20-10 = 58-28/10 = 3
an = a + (n-1) d
a10 = a + (10-1) 3
28 = a + 27
a = 1
Sn = n/2 [2a+(n-1)d]
S30 = 30/2 [ 2(1) + (29) 3]
= 15 [2+87]
= 1335.
Mark as brainliest,if it helped, thank you.
an = a + (n-1) d
a10 = a + (10-1) 3
28 = a + 27
a = 1
Sn = n/2 [2a+(n-1)d]
S30 = 30/2 [ 2(1) + (29) 3]
= 15 [2+87]
= 1335.
Mark as brainliest,if it helped, thank you.
Narattor:
Mark as brainliest,as well, thank you.
Similar questions