If it’s for all of them, starting with number 4, you need to find the common denominator.whatever you times the bottom by, you’ll times the top by. 4 and 7 both can turn into 28 if you multiply the 4 by 7 and the 7 by 4. Now, you multiply the 5 by 4 =20 and the 3 by 7 =21. The fractions turn to 9 and 20 over 28 minus 3 and 21 over 28.