Question

3/4 -3/8 in simplest form?

Answer 1

3/4 and 3/8 have to have equal denominators, so multiply 3/4 by 2/2 because it's equal to one, so it doesn't change the value of the fraction, but it makes the denominator (the number on the bottom) bigger. 
3/4 x 2/2 = 6/8
Now subtract.
6/8 - 3/8 = 3/8
Don't subtract the denominators. 
3/8 can't be simplified. 

Answer 2

$\frac{3}{4}-\frac{3}{8}= \ \ \ \ | make\ common\ denominator\\\\ \frac{6}{8}-\frac{3}{8}=\frac{6-3}{8}=\frac{3}{8}\\\\Solution\ is\ \frac{3}{8}.$