Q7 of 21 Page 208

Suppose 2 kg of sugar contains 9 × 106 crystals. How many sugar crystals are there in


(i) 5 kg of sugar?


(ii) 1.2 kg of sugar?

(i) Let x be the sugar crystals in 5kg of sugar


 


The above information in the form of table is as follows:


 


















Sugar Weight





2 kg





5 kg





No. of crystals





9 × 106 





x



 


The above information are in direct proportion:


 


2/(9 × 106) = 5/x


 


→ x = 22.5 × 106 crystals


or x = 2.25 × 107 crystals 


 


 


 


(ii) Let x be the sugar crystals in 1.2kg of sugar


 


The above information in the form of table is as follows:


 


















Sugar Weight





2 kg





1.2 kg





No. of crystals





9 × 106





x



 


The above information is in direct proportion:


 


Therefore,


 


2/(9 × 106) = 1.2/x


 


→ x = 5.4 × 106 crystals

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