Question
In a class of 40 students, the ratio of boys and girls
is 3 : 2 and the average marks scored by boys is 42 and by girls is 46. Then the average marks scored by the whole class is:Solution
1. Let the number of boys be 3x and girls be 2x, where 3x + 2x = 40 ⇒ x = 8. 2. Then, boys = 24 and girls = 16. 3. Total marks for boys = 24 × 42 = 1008. 4. Total marks for girls = 16 × 46 = 736. 5. Average marks for the class: 
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