40, 45, 50, 55, 65, 75, 75, 100, 100, 100

40, 45, 50, 55, 65, 75, 75, 100, 100, 100. The list above shows the scores of 10 schoolchildren on a certain test. If the standard deviation of the 10 scores is 22.2, rounded to the nearest tenth, how many of the scores are more than 1 standard deviation below the mean of the 10 scores?

This problem repeats another one in the library (at most with different numbers), so it's left out of browsing.

AQuA-RAT — Algebra Question Answering with Rationales (Ling et al., DeepMind, 2017) · train #2678