James buy 7 yard of ribbon
The unitary method is a technique for solving a problem by first finding the value of a single unit, and then finding the necessary value by multiplying the single unit value.
Given:
James= 10 pieces of ribbon
Each of length= 2.1 feet
So, length of 10 ribbons
=2.1*10
=21 feet
Now, 1 yard= 3 feet
So, 21 feet= 21/3= 7 yard
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