In a class, the ratio of rural to urban students is 4 : 7. In the examination, the average percentage marks of the rural and the urban students are respectively 65 and 63. What is the overall percentage marks of the class (correct to two decimal places)?
Show answer & explanation
Correct answer: A
Explanation
The correct answer is Option 1 i.e 63.73%.
Let the number of rural and urban students be 4x and 7x.
Here it is given that the average percentage marks of the rural and the urban students are respectively 65 and 63.
One knows that,
Average = Sum of observation/number of observations.
Average marks of the class = (4x × 65 + 7x × 63)/11x
⇒(260x + 441x)/11x
⇒ 701x/11x = 63.727%
⇒ 63.73%