Apiece of licorice is to be cut into 10 equal size pieces . if the length of the piece of licorice is 2/3 yard, how long will each piece of licorice be?

The first thing to do is turn this into an equation: 
2/3 ÷ 10 

10 as a fraction is 10/1
2/3 ÷ 10/1 = 

Fractional division is just fractional multiplication after switching the numerator and the denominator of the second fraction: 
2/3 X 10/1 

Fractional multiplication is simply multiplying the numerators by each other, and the denominators by each other: 
2 X 10 = 20
3 X 1 = 3

20/3

Each piece of liquorice will be 20/3 or 6 2/3 of a yard long. 

She should use 12/3 to measure