Question 154042
{{{7/12+11/12}}}
={{{(7+11)/12}}}   (as the denominators are the same, simply add the numerators)
={{{18/12}}}
={{{(2*3*3)/(2*2*3)}}}  {factor 18 and 12)
={{{(cross(2)*3*cross(3))/(cross(2)*2*cross(3))}}}
={{{3/2}}}