Question 1206898
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Solving in a much less formal manner than in the other responses....<br>
The 68-95-99.7 rule says that 68% of scores are within 1 standard deviation of the mean.
43 is 1 standard deviation below the mean of 52, so half of 68% = 34% of scores are between 43 and the mean.
That means 50%-34% = 16% of scores are below 43.<br>
ANSWER: 16%<br>