Respuesta :

The common denominator of both fractions is 60.. You can convert 11/12 into 55/60 by multiplying both the numerator and denominator by 5, and you can also convert 7/20 into 21/60 by multiplying both the numerator and denominator by 3.  55/60-21/60= 34/60, simplified to 17/30.

Hope it helped!
First you would find a common denominator, in this case it is 60. So you would multiply 11 and 12 by 5 and 7 and 20 by 3, getting this equation.


55/50 - 21/60


From this equation you would subtract 21 by 55. Getting this fraction as a final answer. 

31/60.

Also if you want a decimal it would be 31 divided by 60. Then you would get your decimal answer being:

0.516666666666666666666666666666666666666666....