Work and Reasoning:
We start off with 12m
Since there are 9 ribbons each 0.4 meters you have to do 9 • 0.4. Since that is 3.6m.
To find out how much ribbon you have left you must subtract the amount he used against the amount he had to begin with.
12 - 3.6 = 8.4
To find out how many wreaths he can make, you must divide the remaining amount of ribbon he has by the 0.6 meter.
8.4 divided by 0.6 is 14.
Answer:
He can make 14 wreaths with the remaining amount of ribbon.