Use the prime factors to determine the lowest common denominator for 2/3 ,7/10 ,5/9 ,11/12

First, let's find the prime factors of the denominators of each fraction:

2/3: 3 is already a prime factor
7/10: 10 = 2 x 5
5/9: 9 = 3 x 3
11/12: 12 = 2 x 2 x 3

Then, the lowest common denominator will be the product of all the unique prime factors with the highest exponent:

2 x 2 x 3 x 5 = 60

Therefore, the lowest common denominator for 2/3, 7/10, 5/9, and 11/12 is 60.