find the sum of 20 terms of A.P whose first term is 4 and common difference is 3
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Answered by
0
Answer:
70
Step-by-step explanation:
sum = n/2(2a + (n-1)d)
= 20/10( 2×4 + 9×3)
2(8+27)
= 2× 35
= 70
Answered by
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Sum of 20th term of A.P. ,where first term(a) =4 and common difference(d) =3
=20/2[2a + (20 – 1)d]
=20/2[8 + (20 – 1)3]
=10[8 + (19)3]
=10[8 + 57]
=10[65]
=650
Formula ,Sum of n terms of AP = n/2[2a + (n – 1)d]
or n/2[a+l] where l is last term of AP.
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