4. \( \mu=84.7 ; \sigma=21.3 \); one standard deviation above the mean

Imagine you're at a fair, and the average score in a game is 84.7. If you pick up an impressive performance, achieving one standard deviation above the mean, your score would soar to 84.7 + 21.3 = 106. It's like leveling up in a game — you've not only met expectations but surpassed them, bringing a sense of pride and accomplishment! In the world of statistics, understanding this concept helps in interpreting data effectively. When you know where one standard deviation lies, you can grasp how data points relate to the average. This knowledge can be beneficial in assessing performance metrics, test scores, or even assessing quality in manufacturing processes, allowing individuals and teams to push their limits and achieve those higher benchmarks!