In the given question, there are several information's of immense importance. based on these information's, the required answer can be easily deduced. It is already given that it takes 3 minutes to sew 1 inches. It is required to find the time required to sew 9 ft.Firstly we have to convert the 9 ft into inches.
1 ft = 12 inches
Then
9 ft = (12 * 9) inches
= 108 inches
To sew 1 inch the time required = 3 minutes
Time required to sew 108 inches = (3 * 108) minutes
= 324 minutes
So it will take 324 minutes to sew 9 ft