Explanation:
multiplying both numerators and denominators of both fractions by any number to get equivalent fractions. let us multiply by 20 so
-2/5 = -40/100 and
2/5 = 40/100
so rational numbers between them
-39/100, -38/100,-37/100.........-3/100,-2/100,-1/100,0,1/100,2/100,3/100................37/100,38/100,39/100
as many as you like you can write