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In an examination average mark of boys is 80 and girls is 60 and average mark of all students is 75 then find the number of boys in the class if number of girls is 18

A54

B52

C65

D105

Answer:

A. 54

Read Explanation:

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boys : girls = 15 : 5

= 3 : 1

since the number of girls is 18

number of boys = 18 × 3 = 54


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