1). $- \frac{{123}}{{325}}$2). $- \frac{{133}}{{325}}$3). $- \frac{{256}}{{650}}$4). $\frac{{256}}{{650}}$

1). $- \frac{{123}}{{325}}$2). $- \frac{{133}}{{325}}$3). \(- \fra

1.	1). $- \frac{{123}}{{325}}$2). $- \frac{{133}}{{325}}$3). $- \frac{{256}}{{650}}$4). $\frac{{256}}{{650}}$
Answer» $(\begin{array}{l} 3\FRAC{1}{{13}} - 4\frac{1}{2} - \left( {1 \div 2\frac{8}{9}} \right) + 1\frac{9}{{25}}\\ = \frac{{40}}{{13}} - \frac{9}{2} - \left( {1 \div \frac{{26}}{9}} \right) + \frac{{34}}{{25}}\\ = \frac{{40}}{{13}} - \frac{9}{2} - \left( {1 \times \frac{9}{{26}}} \right) + \frac{{34}}{{25}}\\ = \frac{{40}}{{13}} - \frac{9}{2} - \frac{9}{{26}} + \frac{{34}}{{25}}\\ = \frac{{40 \times 50 - 9 \times 325 - 9 \times 25 + 34 \times 26}}{{650}}\\ = \frac{{2000 - 2925 - 225 + 884}}{{650}}\\ = \frac{{2884 - 3150}}{{650}}\\ = - \frac{{266}}{{650}} = - \frac{{133}}{{325}} \end{array})$