Chapter 7 is concerned with Birkat HaMazon, the prayer said by Jews after a meal is completed.
Figs, grapes or pomegranates do not require the full Birkat Hamazon, but rather an abbreviated form. If a group of three or more people eat together, they must say Birkat Hamazon. Women, slaves and minors must not be included when counting for the requirement of three mentioned in the previous mishnah. An olive's quantity of food is sufficient to require saying the prayer. The number of people present does not change the blessing that begins Birkat Hamazon. If three are dining together, they should not separate until they are finished with Birkat Hamazon. If a person is dining alone, he should join another group so that they may say Birkat Hamazon together.
Read more about this topic: Berakhot (Talmud)