Write a summary statement about decimal that are equivalent to fraction with denominator of 10 or 100

If the diagram polygon abcd is a reflection across ef to make polygon a'b'c'd'.

Geometry - finding area of regular polygons and sectors (check my math, i can’t find the error)

There are 18 female students and 16 male students in a class. which of the following expresses the ratio of female students to male students in simplest form? а) 10 b) 9 to 8 c) 8: 9 d)18/16