Question

find the rational number between -4,-5

Answer 1

-4/1
-5/1
-4/1×10
-5/1×10
-40/1
-50/1
-41/50
therefore -41/50 is one of the rational number between -4 and -5

Answer 2

there are infinite rational numbers between -4 and -5
we can find them by making denominator equal of -5 and -4 , so
-5×20/1×20 = -100/20
-4×20/1×20 = -80/20
rational numbers are -81/20, -82/20,-83/20........till -99/20 and many more
hope this helps