oh, sorry my answer is wrong :) you can follow the other comment.
Answer:
7
Step-by-step explanation:
1. The easiest way is use calculator:)
or
2.
[tex]factorise \\ \frac{3 \times 7}{7 \times 24} x = \frac{7}{8} \\ \frac{1}{8} x = \frac{7}{8} \\ x = 7[/tex]
