I believe it would just be 102/153.
3 are left.
3/7 means there were 7 slices, but it's missing 4 slices. (Eaten)
i hope this helps :)
Answer:

or in decimal form

Step-by-step explanation:
The midpoint of the line with endpoints
and
is
. just take the average between the points
so given the points (1,0) and (2,-10)




the midpoint is found as follows:




or in decimal form
