Now we have to find out how big andromeda is: on the image below count how many complete (more than 50% full) square arc minutes it takes up.
Image credit: Bill Schoening, Vanessa Harvey/REU program/NOAO/AURA/NSF
Each square on the above picture is a 5 by 5 arc minute square.
If you take the number of stars you worked out for each arc minute for andromeda and times it by the number of arc minutes that andromeda takes up you should get you estimate for the number of stars in andromeda.
Enter the values you got in the boxes below