Answer:
A=41
B=20
C=8
D=3
Step-by-step explanation:
You need to first of all fill the intersection (yellow region). This is the number of people who use both.
This means B=20
Region A is those who use F only. So you must subtract the number who use both.
This means that A=61-20=41
Region C is those who use G+ only.
This means C=28-20=8
Now A+B+C+D=72
This implies that:
41+20+8+D=72
69+D=72
D=72-69
D=3
