It will take them a total of 18 days because if it took them 9 days to make 90 multiply that by 2 to get 180 and you get the answer.
9 = 90
9 x 2 = 18
90 x 2 = 180
you make 180 suits in 18 days
first i plotted all my points on a grid graph
i made sure all of them were in the correct quadrant
then i saw it was a trapezoid or a quadrilateral