The expression NOT equivalent to 10⟌80 is option c. 10/80.
The first option 80 ÷ 10 is equivalent to 8.
The second option 8 is already given.
The third option 10/80 simplifies to 1/8, which is different from 8.
The last option 80/10 is equivalent to 8.
The expression 10/80 is a fraction that simplifies to 1/8, not 8. It represents one-eighth, unlike the original expression 10⟌80, which is equal to 8. Therefore, option c is the one that is NOT equivalent.
The expression that is NOT equivalent to 10⟌80 is 10/80, as it represents a different numerical value, specifically 1/8 instead of 8.