Question 1171222


Machine {{{A}}}:{{{ 10}}} minutes
rate {{{1/10}}} of job in {{{1}}} minute

Machine {{{B +  A = 6 }}}minutes
they do {{{1/6}}} of the job in {{{1}}} minute


Job done by {{{B}}} in {{{1}}} minute =
{{{1/6 -1/10}}}
={{{(10-6)/60}}}
={{{4/60}}}
={{{1/15}}}

so machine {{{B }}}will take {{{15}}} minutes to do the same job