Correct Option: A

On the basis of given graph in question , we have
Here , f₁ = 10 , x₁ = 7 , f₂ = 30 , x₂ = 8 , f₃ = 50 , x₃ = 18 , f₄ = 70 , x₄ = 4 , f₅ = 90 , x₅ = 13

Mid-value of class-interval (x) =	Highest value + Lowest value
	2

∴ Average =	Σ fx
	Σ f

where Σf = Total number of students

Required average marks =	10 × 7 + 30 × 8 + 50 × 18 + 70 × 4 + 90 × 13
	50

Required average marks =	70 + 240 + 900 + 280 + 1170
	50

Required average marks =	2660	= 53.2
	50