To continue our topic on biostatistics, here I will post some good stuff to learn.
Firstly, HERE you will find amazing tutorial. Take a look.
Below you will find a simple introduction to chi-square.
http://www.dpisd.org/cms/lib4/TX01001079/Centricity/Domain/1059/ChiSquarePractice.pdf
http://staff.orecity.k12.or.us/kate.fisher/Ms._Fishers_Website/AP_Biology_files/X2%20Practice%20Problems%20Key.pdf
https://sharepoint.ocsarts.net/student/academic/rima_semaan/honors_biology/Lists/Announcements/Attachments/422/Ch%2011%20Genetics%20and%20Statistics%20(Chi%20Square).pdf
http://www.colby.edu/biology/bi164/Lab/Lab%204Genetics&ChisquareANSWERKEY.pdf