The percentage of the narrow-ruled notebooks that were 1-subject is 49%.
How I found this answer:
The total amount of narrow-ruled notebooks is 209.
There are 102 1-subject narrow-ruled notebooks.
Therefore, it is 102/209.
Divide. 102 divided by 209 = 0.488038278
The problem asked to round to the nearest percent, which would be 49%.
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