30 x 1/5 = <<30*1/5=6>>6 students like Math.
30 x 1/3 = <<30*1/3=10>>10 students like English.
So, 6 + 10 = <<6+10=16>>16 students like either Math or English.
Thus, 30 - 16 = <<30-16=14>>14 students neither like Math nor English.
Since 1/7 of the remaining like Science, therefore 14 x 1/7 = <<14*1/7=2>>2 students like Science.
Hence, 14 - 2 = <<14-2=12>>12 students neither likes the 3 subjects.
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