If John is 30 and twice as old as Maya then Maya is 30 / 2 = <<30/2=15>>15 years old
Drew is 5 years older than Maya so Drew is 15 + 5 = 20 years old
Peter is 4 years older than Drew so is 20 + 4 = 24 years old
In 2 years, Peter will be 24 + 2 = <<24+2=26>>26 years old
Half of Peter’s age in 2 years will be 26 / 2 = <<26/2=13>>13 years old and Jacob’s age in 2 years
Jacob now is 13 - 2 = <<13-2=11>>11 years old
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