28-29day cycle. had sex 3 days after lmp which was 28/7. ovulated 4/5. can sperm live long enough to fertilize egg?

Some will be alive: Nobody knows how long a specific person's sperm will survive in a specific person's body, on a particular day, amongst certain activities... which means it's all an unknown (so, maybe 3-7 days). One can avoid worrying about sperm lifespans, by either using contraception properly if not wanting a baby, or by having sex daily for several days around ovulation time if wanting a baby.