Question 445050
so in one hour she can do 8/4=2 sections
and does 2/8= 1/4 in one hr
and brother can do 8/5=1 3/5=1.6 sections in one hr
1.6/8=1/5 of the job in one hr.

x/4+x/5=1
5x+4x=20
9x=20
x=20/9
x=2 2/9 hrs
if nat works two hrs alone then she has done half the job

which leaves 4 sections to do or 1/2 the job to do
x/4+x/5=1/2
9x=10
x=1 1/9 hrs.
so nat worked 2+1 1/9=3 1/9