Answer:
Step-by-step explanation:
Answer:
120mins
Step-by-step explanation:
Karen mows at 60mins, 1 peice of land
Let Darren mows that 1 peice of land at Xmins
The rate at which Karen mows the land would be 1/60 [takes 60mins for 1 piece]
The rate at which Darren mows the land would be 1/x
The average rate working together on one peice of land will be
the combined time
(1/60) +(1/X) = 1/40
[(1/60) + (1/X)]x40 =1 yard
1/X = 1/40 -1/60=(3-2) /120 =1/120
1/X = 1/120
X=120mins
Darren's takes 120mins
