if necessary. If the denominators of your fractions aren't the same, you'll need to make them the same. List the multiples of each denominator so you can find a number that both denominators have in common. For example, if you're doing 1/4 - 1/5, list all the multiples of 4 and 5 to find 20.  Since the multiples of 4 include 4, 8, 12, 16, 20 and the multiples of 5 include 5, 10, 15, and 20, 20 is the lowest number they have in common. If the denominators are already the same, you can skip straight to subtracting the numerators. Once you've found the lowest common multiple for your unlike fractions, multiply the fraction so the denominator becomes the least common multiple. For example, multiply 1/4 by 5 to get a denominator of 20. You'll also need to multiply the numerator by 5, so 1/4 becomes 5/20. Keep in mind that if you adjust 1 of the fractions in the problem, you'll need to adjust all of the fractions so they're equivalent. For example, if you've adjusted 1/4 to become 5/20, multiply the 1/5 by 4 to get 4/20. The original problem 1/4 - 1/5 becomes 5/20 - 4/20. the numerators and keep the denominator the same. If you started with denominators that were the same or you made equivalent fractions with the same denominator, subtract the numerators. Write the answer and then write the denominator underneath it.  Remember not to subtract the denominators as well. For example, 5/20 - 4/20 = 1/20. Once you have your answer, check to see if you can simplify it. Find the greatest common factor of the numerator and denominator and divide both numbers by it. For example, if you had an answer of 24/32, the greatest common factor is 8. Divide both numbers by 8 to get 3/4. Depending on your answer, you may not be able to simplify it. For example, 1/20 can't be reduced further.
अगर आवश्यक हो, तो दोनों हर के गुणजों (Multiples) की लिस्ट बनाएं: समान हर पाने के लिए अंश तथा हर दोनों की संख्या को समान संख्या से गुणा करें: दिए गए उदाहरण में मौजूद सभी भिन्नों को तुल्य भिन्न (equivalent fractions) में परिवर्तित करें: अंश को घटाएं तथा हर को ऐसे ही रहने दें: उत्तर में मिले भिन्न को सरल रूप में लिखें