Q. 24.0( 107 Votes )

# Determine n if

(i) =12 : 1 (ii) = 11 : 1

Answer :

(i)

Given: =12 : 1

⇒

⇒

⇒

⇒

⇒ 4× (2n—1) = 12×(n-2)

⇒ 8n – 4 = 12n – 24

⇒ 12n – 8n = 24 – 4

⇒ 4n = 20

∴ n = 5

(ii)

Given: =11 : 1

⇒

⇒

⇒

⇒

⇒

⇒

⇒

⇒

⇒ 4× (2n—1) = 11×(n-2)

⇒ 8n – 4 = 11n – 22

⇒ 11n – 8n = 22 – 4

⇒ 3n = 18

∴ n = 6

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