Final answer:
May has walked about 300 miles to the library, rounded to the nearest 10. Numbers 294, 297, and 301 could be rounded to 300 and thus can be the actual miles walked by May. The number 311, however, would not round to 300 and therefore cannot represent about 300 miles walked.
Step-by-step explanation:
The student has posited that May has walked a total of about 300 miles since she started keeping track of her mileage, rounding to the nearest 10 miles. We need to determine if specific numbers could be the actual number of miles walked, assuming May indeed rounds to the nearest 10.
- 294 a-Yes: 294 rounded to the nearest 10 is 290, so this could represent about 300 miles.
- 297 a-Yes: 297 also rounds up to 300, so it could be described as about 300 miles when rounded.
- 301 a-Yes: Similarly, 301 rounds down to 300, so it could be reported as about 300 miles.
- 311 a-No: 311 would round to 310, which is too far from 300 to be considered about 300 miles.
In conclusion, whenever rounding to the nearest ten, the number must fall within the range that would make it round to 300. This range includes any number from 295 through 304.