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Class 10 (Old)

Course: Class 10 (Old) > Unit 5

Lesson 4: Sum of first n terms of an AP
Math
Class 10 (Old)
Arithmetic progressions
Sum of first n terms of an AP
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Comparing arithmetic progressions

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Problem

We have two arithmetic progressions, A and B.
A:2,5,8,11,…B:15,17,19,…\begin{aligned} A &: {2, 5, 8, 11, \dots}\\\\ B &: {15, 17, 19, \dots} \end{aligned}
The n, start superscript, start text, t, h, end text, end superscript terms of both the progressions are equal.
Find the value of n.
n, equals
  • Your answer should be
  • an integer, like 6
  • a simplified proper fraction, like 3, slash, 5
  • a simplified improper fraction, like 7, slash, 4
  • a mixed number, like 1, space, 3, slash, 4
  • an exact decimal, like 0, point, 75
  • a multiple of pi, like 12, space, start text, p, i, end text or 2, slash, 3, space, start text, p, i, end text
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