Final answer:
To represent 6/8 mile on a number line, divide the line into eight equal segments. Mark six of these segments for the distance Kay ran. After two such runs, she has covered 12/8 miles, equal to 1 1/2 miles.
Step-by-step explanation:
The question relates to adding fractions and understanding parts of a number line. To show 6/8 mile on a number line that represents a whole mile, you would divide a number line into eight equal parts. Each of these parts would represent 1/8 of a mile. Kay ran 6/8 of a mile, rested, and ran another 6/8 of a mile. To visually represent this, you would mark six parts out of eight twice on a number line. If we had a number line here, after running twice, she would cover a total of 12/8 miles, which simplifies to 1 4/8 miles or 1 1/2 miles when reduced. Therefore, Kay has run one and a half miles in total.