Answer: 55.4 mins
Step-by-step explanation:
pragnesh and qazi = 2hrs
pragnesh and roghui = 3hrs
qazi and roghui = 4hrs
this means for every 1 hour they wold paint.
pragnesh and qazi =
half of the fence
pragnesh and roghui = 
qazi and roghui =
quarter of the fence
time taken when they all work together
=
+
+ 
= 
= 
= 0.9231 × 60(mins)
= 55.4 mins
Answer:
perpendicular line through a point on a line
Step-by-step explanation:
The circle centered at C seems intended to produce point D at the same distance as point B. That is, C is the midpoint of BD.
The circles centered at B and D with radius greater than BC seems intended to produce intersection points G and H. (It appears accidental that those points are also on circle C. As a rule, that would be difficult to do in one pass.)
So. points G and H are both equidistant from points B and D. A line between them will intersect point C at right angles to AB.
Segment GH is perpendicular to AB through point C (on AB).
It would be true no explanation needed