When you divide a fraction by a fraction, you're really just multiplying by a reciprocal. A reciprocal is the fraction flipped around.
So, 1/8 ÷ 1/4 is the same thing as 1/8 x 4/1
Now, you just multiply. 1 times 4 is 4. 8 times 1 is 8.
1/8 x 4/1=4/8
4/8 simplified is 1/2
So that is how 1/8÷1/4=1/2