हिंदी

The population of a suburb is 16000. Find the rate of increase in the population if the population after two years is 17640.

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प्रश्न

The population of a suburb is 16000. Find the rate of increase in the population if the population after two years is 17640.

योग
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उत्तर

Here, P = Population of a suburb = 16000

A = Population after two years =17640

R = R %

N = 2 years

A = P `(1 + "R"/100)^"N"`

= 17640 = 16000 `(1 + "R"/100)^2`

= `17640/16000` = `(1 + "R"/100)^2`

= `441/400` = `(1 + "R"/100)^2`

Taking square roots from both

= `(1 + "R"/100) =  _-^+(21/20)`

= `"R"/100` = `21/20`

= `"R"/100 =  _-^+ 21/20 - 1`

= `"R" /100 (+ 21/20-1) or (-21/20-1)`

= `"R"/100(1/20) or (-41/20)`

= `"R" = (1/20 xx 100) or (-41/20 xx 100)`

= R = 5 or R = −205

Hence, the rate of increase in the population is 5 p.c.p.a.

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  क्या इस प्रश्न या उत्तर में कोई त्रुटि है?
अध्याय 14: Compound interest - Practice Set 14.2 [पृष्ठ ९३]

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बालभारती Mathematics [English] Standard 8 Maharashtra State Board
अध्याय 14 Compound interest
Practice Set 14.2 | Q 8 | पृष्ठ ९३
बालभारती Mathematics Integrated [English] Standard 8 Maharashtra State Board
अध्याय 14 Compound Interest
Practice Set 14.2 | Q 8. | पृष्ठ ४८

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