Is there supposed to be a picture here?? There isn’t.
Answer:
Step-by-step explanation:
The mode is the number of most repeated data in the set.
Given set 2, 1, 4, 7, 1 has mode 1 (repeated twice).
If we add 1 to the set the mode will remain 1 as it will repeat three times, so the mode won't change.
There is no change in mode, so the mode decrease is zero.