PTC is a substance that has a strong bitter taste for some people and is tasteless for others. The ability to taste PTC is inherited. About 74% of people from a certain country can taste PTC, for example. You want to estimate the proportion of people with at least one grandparent from this country who can taste PTC. (Round your answers up to the nearest person.)

Estimate the sample size required if you made the most conservative assumption about the value of the proportion who could taste PTC.

can someone please help me with this question?