1. 1/4 and 1/2

LCM of 4 and 2 = 4

1/4 = 1*10/4*10 = 10/40

1/2 = 1*20/2*20 = 20/40

5 rational numbers between 1/4 and 1/2 are 11/40, 12/40, 13/40, 14/40, 15/40

2.-2/5 and 1/2

LCM of 2 and 5 = 10

-2/5 = -2*20/5820 = -40/100

1/2 = 1*50/2*50 = 50/100

10 rational numbers are 0/100, 1/100, 2/100, 3/100, 4/100, 5/100, 6/100, 7/100, 8/100, 9/100