Find the sum of the first 20 terms of the A.P | vedclass

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(C) The given $A.P.$ is $50, 46, 42, \ldots$Here,the first term $a = 50$ and the common difference $d = 46 - 50 = -4$.The number of terms $n = 20$.The

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$240$

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(C) The given $A.P.$ is $50, 46, 42, \ldots$Here,the first term $a = 50$ and the common difference $d = 46 - 50 = -4$.The number of terms $n = 20$.The sum of the first $n$ terms of an $A.P.$ is given by the formula $S_n = \frac{n}{2} [2a + (n - 1)d]$.Substituting the values: $S_{20} = \frac{20}{2} [2(50) + (20 - 1)(-4)]$.$S_{20} = 10 [100 + 19(-4)]$.$S_{20} = 10 [100 - 76]$.$S_{20} = 10 [24] = 240$.Therefore,the sum of the first $20$ terms is $240$.

Find the sum of the first $20$ terms of the $A.P.$ $50, 46, 42, \ldots$

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