9th term of an arithmatic progressionvis 9
the sum of 4th and th term and 7th term
is 24 , find the A.p​

1 thought on “9th term of an arithmatic progressionvis 9 <br /> the sum of 4th and th term and 7th term <br />is 24 , find the A.p​”

1. = a + (n-1)d

   where,

   a = the first term of the A.P.

   n = number of terms of the A.P.

   d = difference of consecutive terms of the A.P.

   ⇒ = a + (9-1) d

   ⇒ 19 = a + 8d

   ⇒ 19 – 8d = a ….i.)

   ⇒ = a + (4-1) d

   ⇒ = a + 3d

   [Substituting the value of a from eq. i.)]

   ⇒ = 19 – 8d + 3d

   ⇒ = 19 – 5d

   ⇒ = a + (7-1) d

   ⇒ = a + 6d

   [Substituting the value of a from eq. i.)]

   ⇒ = 19 – 8d + 6d

   ⇒ = 19 – 2d

   Sum of 4th ( ) and 7th term ( ) = 24

   ⇒ + = 24

   [Substituting the value of the terms obtained above]

   ⇒ (19 – 5d) + (19 – 2d) = 24

   ⇒ 19 – 5d + 19 – 2d = 24

   ⇒ 38 – 7d = 24

   ⇒ – 7d = 24 -38

   ⇒ – 7d = -14

   ⇒ d = -14/-7

   ⇒ d = 2

   ⇒ a = 19 – 8d

   ⇒ a = 19 – 8 x 2

   ⇒ a = 19 – 16

   ⇒ a = 3

   First term = a = 3

   Second term = a + d = 3 + 2 = 5

   Third term = a + 2d = 3 + 2 x 2 = 3 + 4 = 7

   Fourth term = a + 3d = 3 + 3 x 2 = 3 + 6 = 9

   Fifth term = a + 4d = 3 + 4 x 2 = 3 + 8 = 11

   Sixth term = a + 5d = 3 + 5 x 2 = 3 + 10 = 13

   Seventh term = a + 6d = 3 + 6 x 2 = 3 + 12 = 15

   The A.P. is –

   3, 5, 7, 9, 11, 13, 15.

   HOPE IT HELPS U….

   MARK AS BRAINLIEST

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