Question 1159580
Printer A can complete {{{1/12}}} of the project in one minute. Printer B can complete {{{1/30}}} of the project. Together, they can complete {{{1/12+1/30=7/60}}} of the project in one minute. So it takes them {{{1/(7/60)=highlight(60/7)}}} minutes, or {{{highlight(8&4/7)}}}.