James is 37-15=<<37-15=22>>22 years old
So 8 years ago he was 22-8=<<22-8=14>>14 years old
That means Janet was 14/2=<<14/2=7>>7 years old 8 years ago
So Janet is now 7+8=<<7+8=15>>15 years old
That means Susan is 15-3=<<15-3=12>>12 years old
So in 5 years she will be 12+5=<<12+5=17>>17 years old
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