Question 1114069
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Informally....<br>
The difference in their ages is 80-54 = 26 years.<br>
When Helen's mother was three times as old as Helen, the difference in their ages was twice Helen's age. (3x-x = 2x)<br>
2x=26 --> x=13; when Helen's mother was 3 times as old as Helen, Helen was 13.<br>
Since Helen is now 54, that was 41 years ago.