1
2
3
4
Correct answer is B
Scores123456No. of students1456x2
Average = 3.5
3.5 = (1×1)+(2×4)+(3×5)+(4×6)+5x+(6×2)1+4+5+6+x+2
3.51 = 1+8+15+24+5x+1218+x
3.51 = 60+5x18+x
60 + 5x = 3.5(18 ÷ x)
60 + 5x = = 63 + 1.5x
5x - 1.5x = 63 - 60
1.5x = 3
x = 31.5
3015 = 2