Given data:
1/4 meters of red fabric
4/5 meters of green fabric
To find how many more meters of green fabric he used you subtract:
Follow the next guide for subtraction of fractions with different denominators:
Subtraction using LCD:
1. List the multiples of the denominators (first 5 multiples):
2. Identify the LCD: In the given case the LCD is 20
3. Rewrite the fractions using the LCD:
To rewrite the fractions, multiply numerator and denominator by the number that makes the denominator be equal to 20
Answer: 11/20 meters