Answer:
A exterior angle of a polygon is an angle outside the polygon formed by one of its sides and the extension of an adjacent side.
As a group they were paid $1000 after putting in 4+6+5+5 = 20 worker-hours.
$1000/(20 worker-hours) = $50/(worker-hour)
Alemu received 4*$50 = $200
Tulu received 6*$50 = $300
Kassa and Tegitu each received 5*$50 = $250
The Solution are : a=3.
b=1.
If you add the two numbers, 10 +8 is 18. The fractional parts are 1/4 and 2/4 which equals 3/4. So the total length is 18 and 3/4 feet.