Answer:
The choice B.
[tex]9 \frac{1}{3} [/tex]
Step-by-step explanation:
[tex]3 \frac{1}{7} + 6 \frac{4}{21} \\ \\ \frac{22}{7} + \frac{130}{21} \\ \\ \frac{66}{21} + \frac{130}{21} = \frac{196}{21} \\ \\ = \frac{196 \div 7}{21 \div 7} = \frac{28}{3} = 9 \frac{1}{3} [/tex]
