मराठी

How Many Terms Are There in the A.P. − 1 , − 5 6 , − 2 3 , − 1 2 , . . . , 10 3 ?

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प्रश्न

How many terms are there in the A.P.\[- 1, - \frac{5}{6}, -\frac{2}{3}, - \frac{1}{2}, . . . , \frac{10}{3}?\] 

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उत्तर

\[- 1, - \frac{5}{6}, - \frac{2}{3}, - \frac{1}{2}, . . . , \frac{10}{3}\]

Here, we have:
a  =\[- 1\]

\[d = \left( \frac{- 5}{6} - \left( - 1 \right) \right) = \left( 1 - \frac{5}{6} \right) = \frac{1}{6}\]

\[ a_n = \frac{10}{3}\]

Let there be n terms in the given A.P.

\[\text { Also }, a_n = a + \left( n - 1 \right)d\]

\[ \Rightarrow \frac{10}{3} = - 1 + \left( n - 1 \right)\frac{1}{6}\]

\[ \Rightarrow \frac{13}{3} = \left( n - 1 \right)\frac{1}{6}\]

\[ \Rightarrow 26 = \left( n - 1 \right)\]

\[ \Rightarrow 27 = n\]

Thus, there are 27 terms in the given A.P.

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पाठ 19: Arithmetic Progression - Exercise 19.2 [पृष्ठ १२]

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आर.डी. शर्मा Mathematics [English] Class 11
पाठ 19 Arithmetic Progression
Exercise 19.2 | Q 6.2 | पृष्ठ १२

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