First, find the least common denominator (the denominator that can be able to equal to other denominators).
[tex]4[tex] [tex]\frac{1}{3}[tex]
[tex]4[tex] [tex]\frac{5}{15}[tex]
Then, subtract.
[tex]4[tex] [tex]\frac{5}{15}[tex] [tex]-[tex] [tex]1[tex] [tex]\frac{7}{15}[tex]
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= [tex]2[tex] [tex]\frac{13}{15}[tex]