Question

Tính.

a) 536 817 + 82 579                    981 759 – 645 267

b) 64,38 + 93,46                          86,09 – 54,3

c) \(\dfrac{4}{7}+\dfrac{3}{5}\)                                     \(\dfrac{10}{9}-\dfrac{5}{6}\)

Answer 1

a) 536 817 + 82 579 = 619 396

981 759 – 645 267 = 336 492

b) 64,38 + 93,46 = 147,84

86,09 – 54,3 = 31,79

c) $\frac{4}{7} + \frac{3}{5} = \frac{{4 \times 5}}{{7 \times 5}} + \frac{{3 \times 5}}{{5 \times 7}} = \frac{{20}}{{35}} + \frac{{15}}{{35}} = \frac{{35}}{{35}} = 1$

$\frac{{10}}{9} - \frac{5}{6} = \frac{{10 \times 2}}{{9 \times 2}} - \frac{{5 \times 3}}{{6 \times 3}} = \frac{{20}}{{18}} - \frac{{15}}{{18}} = \frac{5}{{18}}$