2 Multiple choice 1 point 1Qscores are normally distributed with mean 100 and standard deviation 15 . Find the probability of an IQ score falling between 90 and 110 . 0.3187 0.5050 0.6813 0.4950

To determine the probability of an IQ score falling between 90 and 110 in a normal distribution, we first convert the IQ scores into z-scores. For 90, the z-score is (90-100)/15 = -0.67, and for 110, it's (110-100)/15 = 0.67. Using a z-table or normal distribution calculator, we find the probabilities corresponding to these z-scores. The probability of being between these z-scores (from -0.67 to 0.67) is approximately 0.5050. Therefore, the correct answer is **0.5050**. **Fun Fact:** The concept of IQ (Intelligence Quotient) dates back to the early 20th century, invented by French psychologist Alfred Binet. Originally, it aimed to identify students needing extra academic support, showcasing how science has evolved in understanding intelligence! **Practical Insight:** Understanding normal distribution isn't just for academic exercises; it’s crucial in areas like educational assessments, where measuring cognitive abilities can help tailor teaching methods, allowing educators to cater to diverse learning needs effectively!