Which of the sequence 20,19 1/2, 18 1/2, 17 3/4 is the first negative

1.	Which of the sequence 20,19 1/2, 18 1/2, 17 3/4 is the first negative term
Answer» The given sequence is an A.P. in which first term a = 20 and common difference d =\xa0{tex}-\\frac34{/tex}Let the nth term of the given A.P. be negative thenT\u200b\u200b\u200b\u200b\u200b\u200bn\u200b\u200b\u200b\u200b\u200b < 0a+(n-1)d<020+(n-1)({tex}-\\frac34{/tex})<0On multiplication by 4 we get80-3n+3<083-3n<083<3nOr 3n>83{tex}n > \\frac{83}{3}{/tex}n > 27.67Hence 28th term will be first negative term

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