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The total number of leaves that was collected by Lisa is the product of the number of days in a week and the number of leaves she collected per tree. This is shown below,
(7 trees / week) x (7 leaves / 1 tree) = 49 leaves / week
Thus, Lisa collected 49 leaves in a week.
Answer:
9/20 = 0.45
Step-by-step explanation:

The 7 friends would get 1.4m of ribbon.
You would have to do 2.4 divided by 12 to get 0.2. Then multiply 0.2 by 7 to get 1.4.