6) \( 1 \frac{11}{18} + \frac{7}{15} \) = \( 1 \frac{55}{90} + \frac{42}{90} \) = \( 1 \frac{97}{90} \) = 2 \(\frac{7}{90}\)

6) \( 1 \frac{11}{18} + \frac{7}{15} = 1 \frac{11 \cdot 5}{18 \cdot 5} + \frac{7 \cdot 6}{15 \cdot 6} = 1 \frac{55}{90} + \frac{42}{90} = 1 + \frac{55+42}{90} = 1 \frac{97}{90} = 1 + 1 \frac{7}{90} = 2 \frac{7}{90} \)