Question 866725
The other tutor's solution is probably the one expected, but,
4 times older = 5 times as old.
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Is 1 time older the same age?
4 times older = a 400% increase in age = 5 times as old.
Be careful of that.
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PS  A thing can't be 10 times smaller, since 1 time smaller is zero.
This is what's known as GIBBERISH.