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If (x + 1), 3x and (4x + 2) are first th...

If `(x + 1), 3x and (4x + 2)` are first three terms of an A.P. then its `5^(th)` term is

A

14

B

19

C

24

D

28

Text Solution

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The correct Answer is:
To solve the problem step by step, we will follow the properties of an Arithmetic Progression (A.P.). ### Step 1: Identify the terms The first three terms of the A.P. are given as: - First term (a) = \( x + 1 \) - Second term (b) = \( 3x \) - Third term (c) = \( 4x + 2 \) ### Step 2: Use the property of A.P. In an A.P., the difference between consecutive terms is constant. Therefore, we can set up the equation: \[ b - a = c - b \] Substituting the terms: \[ 3x - (x + 1) = (4x + 2) - 3x \] ### Step 3: Simplify the equation Now, simplify both sides: - Left side: \[ 3x - x - 1 = 2x - 1 \] - Right side: \[ 4x + 2 - 3x = x + 2 \] So, we have: \[ 2x - 1 = x + 2 \] ### Step 4: Solve for \( x \) Now, isolate \( x \): \[ 2x - x = 2 + 1 \] \[ x = 3 \] ### Step 5: Find the first term and common difference Now that we have \( x \), we can find the first term and the common difference: - First term \( a = x + 1 = 3 + 1 = 4 \) - Second term \( b = 3x = 3 \times 3 = 9 \) - Third term \( c = 4x + 2 = 4 \times 3 + 2 = 12 + 2 = 14 \) Now, calculate the common difference \( d \): \[ d = b - a = 9 - 4 = 5 \] ### Step 6: Find the fifth term The formula for the \( n^{th} \) term of an A.P. is given by: \[ T_n = a + (n - 1)d \] For the fifth term (\( n = 5 \)): \[ T_5 = 4 + (5 - 1) \times 5 \] \[ T_5 = 4 + 4 \times 5 \] \[ T_5 = 4 + 20 = 24 \] ### Final Answer The fifth term of the A.P. is \( \boxed{24} \).

To solve the problem step by step, we will follow the properties of an Arithmetic Progression (A.P.). ### Step 1: Identify the terms The first three terms of the A.P. are given as: - First term (a) = \( x + 1 \) - Second term (b) = \( 3x \) - Third term (c) = \( 4x + 2 \) ...
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