Question

Find the Thenth term between the arthemetic series 3+7+11+15+.... and 1+6+11+16....

Answer 1

Answer:

191

Step-by-step explanation:

First Arthemetic series = 3 + 7 + 11 + 15 +.....

Here, common diffrence, d = 4.....(i)

Second Arthemetic series = 1 + 6 + 11 + 16+.....

& common diffrence of this series is 5.....(ii)

Series of common term is 11 + ...... [we have to find a₁₀]

Now, take the LCM of i & ii

LCM of 4 and 5 = 20

Now, This 20 will become common diffrence for the common term series.

Here, a = 11 [first term of common term]

and, d =  20

As, tn = a + (n - 1 ) d

=> t₁₀ = 11 + (10 - 1) 20

=> t₁₀ = 11 + 180

=> t₁₀ = 191

Thus, 191 is 10th common term in both series.

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Amrit______