Respuesta :
You just have to find the lcm or least common factors of the denominators which is 60.
The least common multiple of denominators
.. 4 = 2^2
.. 5
.. 6 = 2*3
.. 15 = 3*5
.. 20 = 2^2*5
is 2^2*3*5 = 60
The lowest common denominator is 60.
.. 4 = 2^2
.. 5
.. 6 = 2*3
.. 15 = 3*5
.. 20 = 2^2*5
is 2^2*3*5 = 60
The lowest common denominator is 60.