$\frac{13}{8}$ - $\frac{2}{9}$ × $\frac{6}{4}$ + $\frac{1}{3}$
=$\frac{13}{8}$ - $\frac{2×6}{9×4}$ + $\frac{1}{3}$
= $\frac{13}{8}$ - $\frac{1}{3}$ + $\frac{1}{3}$
= $\frac{31}{24}$ + $\frac{1}{3}$
= $\frac{13}{8}$
7 × x +9 × x = 175+65
7 × x +9 × x = 240
(7+9) × x = 240
16 × x = 240
x = 240 ÷ 16
x = 15
Chúc bạn học tốt!