from 13 friends to 14 friends. The number of friends is increased by 1.
To get the percentage of increase:
(14 - 13) / 13 = 1 / 13 = 0.0769 * 100% = 7.69%
The increase of 1 friend is equivalent to 7.69% increase.
13 is the basis. It is the 100%
1 is the increase. It is the 7.69%
14 is the total number of friends. It is the 107.69% = 100% + 7.69%
