Latex Coder 2

Posted byjaehwa
What is $\displaystyle {9}\frac{2}{7} - {8}\frac{1}{7}$?
A. $ {1}\dfrac{1}{7}$
B. $ {2}\dfrac{1}{7}$
C. $ \dfrac{1}{7}$
D. ${1}\dfrac{5}{7}$
E. $ {2}\dfrac{5}{7}$