Given a=5, d=3, an=50, find n and SN

1.	Given a=5, d=3, an=50, find n and SN
Answer» Given a=5,d=3an=50We knowa\u200b\u200b\u200b\u200b\u200b\u200bn\xa0= a+(n-1)d=> 50 = 5+(n-1)3=> 45 = (n-1)3=> 15 = n-1=> n = 16{tex}=> S_ {16}= {16\\over 2}[2\\times 5+(16-1)3]\\\\=> S_{16}=8[10+45]\\\\=> S_{16}=440{/tex} a = 5 d = 3 an = 50 n = ? Sn = ?an = a + (n -1)d50 = 5 + (n - 1)345/3 = n - 115 + 1 = nn = 16Sn = n/2(2a + (n - 1)d S16= 16/2(10 + 15x3) = 8 x 55 = 440\xa0 N=10 and SN=0.1

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