Let the number of boys be 4x and number of girls be 6x Given, 4x+6x=50 x=5 Number of boys =20 and number of girls =30 Average marks of girls =60 Total marks scored by girls =60times30=1800 Average marks score by batch =62 Total marks scored by batch =62times50=3100 Marks scored by boys =3100−1800=1300 Average marks of boys