Chinese education. The Programme for International Student Assessment (PISA) is a triennial global survey of 15-year-old students to assesses the extent of key knowledge and skills essential for full participation in society. According to PISA 2018 results, average mathematics proficiency of youth among the 79 participating countries equals 489, with a standard deviation of 91, whereas average reading proficiency equals 487, with a standard deviation of 99.

Four provinces in China—Beijing, Shanghai, Jiangsu, and Zhejiang—

outperformed all other 78 education systems, scoring 591 and 555 for mathematics and reading, respectively. Which score is more unusual? Explain. (Data in Pisa 2018 Results.)