3/4 minus 3/5 as a fraction

The below workout with step by step calculation shows how to find what is 3/4 minus 3/5 in simplest form by using the following methods:
1. LCM method,
2. Cross multiplication method.

Problem and Workout - LCM Method:
What is 3/4 minus 3/5 as a fraction?

step 1 Observe the input parameters and what to be found:
Input:
Fraction A: 3/4
Fraction B: 3/5

What to be found?
3/4-3/5 = ?
Find what's the difference between 3/4 and 3/5.

step 2 Compare the denominators of fractions 3/4 and 3/5 to identify whether it is a like or unlike fraction subtraction. Since the denominators of given fractions 3/4 and 3/5 are not equal, it is said to be unlike fractions subtraction.

step 3For unlike fractions subtraction, find the LCM (least common multiple) of both denominators of fractions 3/4 and 3/5:
The LCM of 4 and 5 is 20.

step 4 Write the fractions 3/4 and 3/5 in the subtraction expression form and multiply LCM with all the numerators and denominators of both fractions.
=3/4-3/5
=(3 x 20)/(4 x 20)-(3 x 20)/(5 x 20)

step 5 Simplify the expression to have common denominator:
=15/20-12/20

step 6 Take the common values out and rewrite the above expression like the below:
=1/20 x (15/1-12/1)
=1/20 x (15 - 12)

step 7Simplify the above expression further:
=1/20 x 3
=3/20
3/4-3/5=3/20

Hence,
3/4 minus 3/5 equals to 3/20 in fraction.

Problem and Workout - Cross Multiplication Method
step 1 Observe the input parameters and what to be found:
Input:
Fraction A: 3/4
Fraction B: 3/5

What to be found?
3/4-3/5 = ?
Find what's the difference between 3/4 and 3/5.

step 2 Find the product of numerator of Fraction A and denominator of Fraction B (3 x 5), find the product of numerator of Fraction B and denominator of Fraction A (3 x 4), and find the product of both denominators of Fraction A and Fraction B (4 x 5) and rewrite the equation as like the below:
= (3 x 5) - (3 x 4)/(4 x 5)

step 3 Simplify and rewrite the fraction:
= (15 - 12)/20
3/4-3/5 = 3/20
Hence,
3/4 minus 3/5 = 3/20