the first and the last term of an AP are 17 and 350 respectively if the common difference is 9 how many terms are thare and what is their sum
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Answered by
3
a=17 & d=9
tn=17+(n-1)9
350=17+9n-9
342=9n
n=38
There are 38 terms
Sum=n/2{2a+(n-1)d}
Sum=38/2{2×17+(38-1)9}
Sum=19{34+333}
Sum=19(367)
Sum=6973
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tn=17+(n-1)9
350=17+9n-9
342=9n
n=38
There are 38 terms
Sum=n/2{2a+(n-1)d}
Sum=38/2{2×17+(38-1)9}
Sum=19{34+333}
Sum=19(367)
Sum=6973
Mark me as brainliest if it's help you!!!!
Answered by
1
a=t1 =17 d=9 tn=350
tn=a+(n-1)d 350=17+(n-1)9
350-17=(n-1)9
333=(n-1)9
333/9 = n-1
37=n-1
37+1=38
n=38
Sn=n/2[t1+tn]
S38=38/2[17+350]
S38=19×367
S38=6973
tn=a+(n-1)d 350=17+(n-1)9
350-17=(n-1)9
333=(n-1)9
333/9 = n-1
37=n-1
37+1=38
n=38
Sn=n/2[t1+tn]
S38=38/2[17+350]
S38=19×367
S38=6973
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