Question

4. Find the 19th term of the following A.P.
7, 13, 19, 25,...
5. Find the 27" term of the following A.P.
9, 4, -1, -6, -11,...​

Answer 1

Answer for Question Number: 4

Given:

1. First term = a = 7
2. Common Difference = d =  13 - 7 = 6

To find:

• 19th term = ?

Method:

aₙ = a + (n - 1)d

⇒ a₁₉ = 7 + (19 - 1)6

⇒ a₁₉ = 7 + (18)6

⇒ a₁₉ = 7 + 108

⇒ a₁₉ = 115

∴ 19th term = 115

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Answer for Question Number 5

Given:

• First term = a = 9
• Common Difference = d = 4 - 9 = -5

To find:

• 27th term = a₂₇ = ?

Method:

aₙ = a + (n - 1)d

⇒ a₂₇ = 9 + (27 - 1)-5

⇒ a₂₇ = 9 + 26(-5)

⇒ a₂₇ = 9 - 130

⇒ a₂₇ = -121

∴ 27th term = -121