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Tamil Nadu Board of Secondary EducationSSLC (English Medium) Class 8

If the present population of a city is P and it increases at the rate of r% p.a, then the population n years ago would be P(1+r100)n - Mathematics

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Question

If the present population of a city is P and it increases at the rate of r% p.a, then the population n years ago would be `"P"(1 + "r"/100)^"n"`

Options

  • True

  • False

MCQ
True or False
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Solution

False

Explanation;

Hint:

Let the population ‘n’ years ago be ‘x’

∴ Present population (P) = `x xx (1 + "r"/100)^"n"`

∴ x = `"P"/(1 + "r"/100)^"n"`

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Chapter 4: Life Mathematics - Exercise 4.3 [Page 139]

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Samacheer Kalvi Mathematics [English] Class 8 TN Board
Chapter 4 Life Mathematics
Exercise 4.3 | Q 2. (ii) | Page 139

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