Final answer:
The distance between -7 and 13 on a number line is 20 units.
Step-by-step explanation:
To find the distance between -7 and 13 on a number line, we need to subtract the smaller number from the larger number. In this case, 13 - (-7) = 13 + 7 = 20. Therefore, the distance between -7 and 13 on a number line is 20 units.
Learn more about Finding distance on a number line