1. The problem statement, all variables and given/known data G is a group. H is a subgroup. lHl= order of H lGl=order of G [G]=Number of cosets Counting Formula lGl = lHl [G] I have a question of clarification about this formula. My book says that [G]=number of cosets. The problem is that at this point in my book they haven't defined right cosests yet so I wasn't sure if [G]= The sum of the rights cosests and left cosets? or [G]= Just the left cosets? Thank you.