7.4 is your final answer, hope that help, one decimal place is the first number after the decimal.
There are 4 possibilities:
1) No event happens
2) event A happens, not event B
3) event B happens, not event A
4) both events happen
seeing as there is a 50% chance of either event happening, I would assume that all 4 possibilities have an equal chance of happening
so if there are 4 events, then each one is 25% likely.
So the probability if them both occurring is 25%
I think
