If the sum of first 14 terms of an AP is 1078 & its 1st term is 12, find a20
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Sum of first 14 terms=1078
a=12
Sum of 14 terms=n/2[2a+(n-1)d]
1078 =14/2[2(12)+(14-1)d]
1078=7[24+13d]
24+13d=1078÷7
13d=154-24
13d=130
d=10
a20=a+19d
=12+19(10)
=12+190
=202
Hence,the 20th term is equal to 202.
I hope my answer helps you buddy
a=12
Sum of 14 terms=n/2[2a+(n-1)d]
1078 =14/2[2(12)+(14-1)d]
1078=7[24+13d]
24+13d=1078÷7
13d=154-24
13d=130
d=10
a20=a+19d
=12+19(10)
=12+190
=202
Hence,the 20th term is equal to 202.
I hope my answer helps you buddy
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