Asked by Elijah

The 9th And 22nd Term Of An A.P Are 29 And 55 Respectively. Find The Sum Of It's First 60 Terms
Answered by MathMate
T(9)=29.............9th term
T(22)=55............22nd term
If the AP is T(n)=T(n-1)+d, then
d=(T(22)-T(9))/(22-9)=26/13=2

T(1)=T(9)-(9-1)d = 13
and therefore
T(n)=11+2n
T(1)=13
T(60)=11+120=131
To find the sum of the 1st to the 60th term, we use Little Gauss's method:
T(1)+T(2)+....T(30)
T(60)+T(59)+...T(31)
-----------------------(add)
T(1)+T(60) + T(2)+T(59) + ...(30 times)
=30(13+131)=4320

Answered by Matins Uche rosemary
Is the answer correct because my teacher did not teach me like this. Please answer me
Answered by Winnie
That method is soo incorrect for solving sum on an AP
You didn't even find the first term and common difference
Answered by [email protected]
i'm in doubt of it correctness
can u make the answer more simplified? it a bit mesmerising.
Answered by Favour
The method is so incorrect I don't know how you got your answers
Answered by Mercy
That's nice and correct,gud!!!!!
Answered by Mercy
Correct that's nice,gud!!!!!!!!!
Answered by Abdullahi
Answer
Answered by Abdulhadi
Nearest
Answered by mfon
incorrect
Answered by Anonymous
your answer is correct, because i am a mathematician

Answered by Anonymous
You are out of point