Posted by
**christine** on
.

In 1995, more than 1.1 million students in the U.S. took the SAT. On the mathematics section, the mean =507, s=112 (standard deviation). Students receive scores rounded to the nearest 10. What is the interval of student scores that lie within one standard deviation of the mean?

That would be the interval from 507-112 = 395, to 507+112 = 619. If you round both ends of that interval to the nearest 10, it would be 400 to 620.