## Comparing different sized samples, statistics help needed.

It has been a long time since I've done any statistics, so apologies in advance if I'm asking elementary questions.

I wanted to do some nice statistics for a charity event that was held. The data I have is:

Group A, 20 volunteers (total people in group 100 people.)
Group B, 15 volunteers (total size of group 50 people.)
Group C, 10 volunteers (total size of group 30 people.)
Group D, 5 volunteers (total size of group 20 people.)

I have shown a breakdown of how many people volunteered per group.
e.g. # of volunteers / total # of volunteers,
Group A: 20/50 = 40% of volunteers were from Group A
Group B: 15/50 = 30% of volunteers were from Group B
Group C: 10/50 = 20% of volunteers were from Group C
Group D: 5/50 = 10% of volunteers were from Group D

This shows that Group A has contributed the most amount of volunteers. However, this doesn't take into account the size of the groups. So, I calculated the number of volunteers relative to size of the group.

Volunteers (relative to size of the group)
Group A, 20/100 = 0.2 (20% of people in this group volunteered)
Group B, 15/50 = 0.3 (30% of people in this group volunteered)
Group C, 10/30 = 0.33 (33% of people in this group volunteered)
Group D, 5/20 = 0.25 (25% of people in this group volunteered)

From this view, Group C has contributed the most amount of volunteers (per # of people.)

How can I represent this data?
There has been a total of (20+15+10+5) 50 volunteers, from 200 people (group A+B+C+D). So only 25% of people volunteered for the event.

I want to show statistics around this 25% of people, relative to the amount of people per groups.

Can you recommend other analysis that I should perform?

Any help (or reference to the types of topics that I should study) would be appreciated.

Thank you
 PhysOrg.com science news on PhysOrg.com >> Leading 3-D printer firms to merge in $403M deal (Update)>> LA to give every student an iPad;$30M order>> CIA faulted for choosing Amazon over IBM on cloud contract

Recognitions: