221. If A : B = 7 : 9 and B : C = 3 : 5 then A : B : C is ?

1. 1. 7 : 9 : 5

   
   
   

   2. 21 : 35 : 45

   
   
   

   3. 7 : 9 : 15

   
   
   

   4. 7 : 3 : 15

   
   
   

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1. View Hint View Answer Discuss in Forum

   A : B = 7 : 9
   and B : C = 3 : 5 = 9 : 15
   

   Correct Option: C

   A : B = 7
   and B : C = 3 : 5 = 9 : 15
   ∴ A : B : C = 7 : 9 : 15

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222. 0.6 of a number equals 0.09 of another number. The ratio of the number is ?

1. 1. 2 : 3

   
   
   

   2. 1 : 15

   
   
   

   3. 20 : 3

   
   
   

   4. 3 : 20

   
   
   

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1. View Hint View Answer Discuss in Forum

   0.6 x a = 0.09 x b

   Correct Option: D

   0.6 x a = 0.09 x b
   ∴ a/b = 0.09 / 0.06 = 9 / 60 = 3 / 20 = 3 : 20

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223. If 10% of A is the same as 20% of B then A : B is equal to ?

1. 1. 1 : 2

   
   
   

   2. 2 : 1

   
   
   

   3. 5 : 1

   
   
   

   4. 10 : 1

   
   
   

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1. View Hint View Answer Discuss in Forum

   10% of A = 20% of B
   ⇒ 10/100 x A = 20/100 x B

   Correct Option: B

   10% of A = 20% of B
   ⇒ 10/100 x A = 20/100 x B
   ⇒ A/10 = B/5
   ∴ A/B = 10/5 = 2
   Hence, A : B = 2 : 1

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224. If A : B = 2 : 3 and B : C =4 : 5, then C : A is equal to ?

1. 1. 15 : 8

   
   
   

   2. 12 : 10

   
   
   

   3. 8 : 5

   
   
   

   4. 8 : 15

   
   
   

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1. View Hint View Answer Discuss in Forum

   A/B = 2/3 and B/C = 4/5
   ∴ A/C = (A/B) x (B/C) = (2/3) x (4/5) = (8/15)
   So, C : A = 15 : 8

   Correct Option: A

   A/B = 2/3 and B/C = 4/5
   ∴ A/C = (A/B) x (B/C) = (2/3) x (4/5) = (8/15)
   So, C : A = 15 : 8

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225. The proportion of Zinc and Copper in a brass piece is 13 : 7. How much zinc will be there in 100 kg of such a piece ?

1. 1. 20 kg

   
   
   

   2. 35 kg

   
   
   

   3. 55 kg

   
   
   

   4. 65 kg

   
   
   

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1. View Hint View Answer Discuss in Forum

   ∵ 20 kg of brass contains zinc = 13 kg
   ∴ 100 kg of brass contains zinc = (13/20) x 100 kg.

   Correct Option: D

   ∵ 20 kg of brass contains zinc = 13 kg
   ∴ 100 kg of brass contains zinc = (13/20) x 100 kg. = 65 kg.

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