We technically can't tell! Just because a pattern (increasing by two faces for every new pattern) is true at first doesn't mean it holds forever. However, if we make the assumption that the number of smiley faces continues to increase by 2, we have 4+87*2=177 as the answer, since we start with four and continue through a total of 87 more patterns, each of which adds two more faces.
We technically can't tell! Just because a pattern (increasing by two faces for every new pattern) is true at first doesn't mean it holds forever.
However, if we make the assumption that the number of smiley faces continues to increase by 2, we have 4+87*2=177 as the answer, since we start with four and continue through a total of 87 more patterns, each of which adds two more faces.