With some simple rearrangement, we can rewrite the numerator as

Then factorizing the difference of squares,
, we end up with

Answer: A B
Group 1 0.25 0.75
Group 2 0.44 0.56
Step-by-step explanation:
Since we have given that
Number of people of A in group 1 = 15
Number of people of B in group 1 = 45
Total number of people in group 1 is given by

Relative frequency of people of A in Group 1 is given by

Relative frequency of people of B in Group 1 is given by

Similarly, Number of people of A in group 2 = 20
Number of people of B in group 2 = 25
Total number of people in group 2 is given by

Relative frequency of people of A in Group 2 is given by

Relative frequency of people of B in Group 2 is given by

Hence, A B
Group 1 0.25 0.75
Group 2 0.44 0.56
Depends where. Normally it whould cost 17,500.