मराठी

Is 68 a Term of the A.P. 7, 10, 13, ...?

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प्रश्न

Is 68 a term of the A.P. 7, 10, 13, ...?

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उत्तर

7, 10, 13...
Here, we have:
a = 7

\[d = \left( 10 - 7 \right) = 3\]

\[\text { Let } a_n = 68\]

\[ \Rightarrow a + (n - 1) d = 68\]

\[ \Rightarrow 7 + (n - 1)(3) = 68\]

\[ \Rightarrow (n - 1)(3) = 61\]

\[ \Rightarrow (n - 1) = \frac{61}{3}\]

\[ \Rightarrow n = \frac{61}{3} + 1 = \frac{64}{3}\]

Since n is not a natural number.So, 68 is not a term of 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 4.1 | पृष्ठ १२

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