Answer:
The total of people is the 100%.
68% owns a tv.
72% owns radios.
12% does not own anything.
Now, if we add those, we have:
12% + 68% + 72% = 152%.
This is larger than the 100%, then this means that there is a percentage of people that have both Tv and Radio, this percentage is:
152% - 100% = 52%
We have a surpass because we are adding those 52% two times (because they belong in two different groups)
So, the table is:
68% owns a tv.
72% owns a radio.
12% does not own anything.
52% owns both, radio and tv.
68% - 52% = 16% owns only tv.
72% - 52% = 20% owns only radio.
Then the Venn diagram consist in two circles, one with the 72%, other with the 68%, in such way that the circles have an intersection of the 52%.