Harry's father is 50 years + 24 years = <<50+24=74>>74 years old.
Harry's mother is 1/25 * 50 years = <<1/25*50=2>>2 years younger than his father.
So she is currently 74 years - 2 years = <<74-2=72>>72 years old.
So when Harry was born, she was 72 years - 50 years = <<72-50=22>>22 years old.
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