Study the following table and answer the question:

Percentage of marks obtained by six students in five subjects A, B, C, D & E.

Students	Subject
	A (out of 75)	B (out of 80)	C (out of 100)	D (out of 50)	E (out of 150)
Manju	68	85	86	72	92
Amit	64	65	80	96	80
Rekha	88	75	65	74	90
Anuj	80	55	68	66	84
Abhi	72	65	72	54	74
Vikram	60	70	73	84	86

The average marks of Manju, Rekha and Abhi in subject B are?