The regular pentagon shown has a side length of 2 cm.
The perimeter of the pentagon is
Problem 7
Pick one
Official solution
Arranging the five answers along with 10 from smallest to
largest, we get $1, 5, 8, 10, 13,
19$.
Since 10 is 2 more than 8 and 10 is 3 less than 13, then 8 is the
closest number to 10.