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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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Finding first term and common difference when sum is given

Google Classroom

Problem

In an arithmetic sequence:
S, start subscript, 20, end subscript, equals, 500
a, start subscript, 20, end subscript, equals, 44
Find the first term, a, start subscript, 1, end subscript, of the sequence.
a, start subscript, 1, end subscript, 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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