Question

Simplify:

\[\frac{7}{9} + \frac{3}{- 4}\]

Answer 1

\[\frac{7}{9} + \frac{3}{- 4} = \frac{7}{9} + \frac{- 3}{4}\]
\[\text{L.C.M. of thedenominators 9 and 4 is 36}.\]
\[\text{Now, we willexpress}\frac{7}{9}\text{and}\frac{- 3}{4}\text{in the form in which they take thedenominator 36.}\]
\[\frac{7 \times 4}{9 \times 4} = \frac{28}{36}\]
\[\frac{- 3 \times 9}{4 \times 9} = \frac{- 27}{36}\]
\[\text{So}\]
\[\frac{7}{9} + \frac{- 3}{4} = \frac{28}{36} + \frac{- 27}{36}\]
\[ = \frac{28 + ( - 27)}{36}\]
\[ = \frac{28 - 27}{36}\]
\[ = \frac{1}{36}\]