Question 189591
You're on the right track. What you've found is that the scores between 76 and 88 fall within 2 standard deviations of the mean. Since these scores are normally distributed (ie they fall on the bell curve), this means that 95% of the scores fall between 76 and 88



Note: 68% of scores fall within 1 standard deviation within the mean. Also, 95% of scores fall within 2 standard deviations within the mean. Finally, 99.7% of scores fall within 3 standard deviations within the mean (these are all approximations of course). This is called the 68-95-99.7 rule or the empirical rule. Unfortunately, this is something to be memorized (but it's very important in statistics)