It took him 2*.75=<<2*.75=1.5>>1.5 years longer to do his research than it took to learn the basics
So it took him a total of 2+1.5=<<2+1.5=3.5>>3.5 years to do research
His dissertation took 1/2 = <<1/2=.5>>.5 years to write
So everything together took 1+2+3.5+.5=<<1+2+3.5+.5=7>>7 years
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