Cristina can simplest form it again by 2. So it's 2/5 long.
Actual length of textbook is 5 2 long ;
Cristina's measurement of 10 4 is not in simplest form. The correct measurement in simplest form is 5 2 . This was found by identifying the greatest common factor of 4 and 10, which is 2, and simplifying the fraction accordingly.
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