If 10 workers are working 2 hours a day, then that's 20 hours a day. That times the 5 days it took is 100 hours to finish the repair. SO the 2 workers working 5 hours each is 10 hours a day. To get the necessary 100 hours at that pace, they work 10 days.
lThe area of the triangles is 3/2 x 2.6 = 3.9/2 = 1.95. since there is 2 triangle do 1.95 x 2 = 3.9. and the area of the square is 3x3 = 9. All in all, 3.9 + 9 = 12.9.
