dó 0 teenr hả mày 

\(\frac{35}{28}-\frac{48}{64}=\frac{5}{4}-\frac{3}{4}=\frac{1}{2}\)

\(\dfrac{7}{15}+\dfrac{4}{5}\)

\(=\dfrac{7}{15}+\dfrac{12}{15}\)

\(=\dfrac{19}{15}\)

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\(\dfrac{35}{28}-\dfrac{48}{64}\)

\(=\dfrac{2240}{1792}-\dfrac{1344}{1792}\)

\(=\dfrac{896}{1792}=\dfrac{1}{2}\)

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\(\dfrac{10}{13}:\dfrac{3}{4}\)

\(=\dfrac{10}{13}\)x\(\dfrac{4}{3}\)

\(=\dfrac{40}{39}\)

19/15

1/2

40/39

4(bấm máy tính)

tick giùm mình nha!

a) \(28-\left(-32\right)+\left(-28\right)-32+5=28+32-28-32+5\)

\(=5\)

b) \(48-\left(-52\right)+64+\left(-34\right)\)\(=48+52+64-34\)

\(=130\)

k mình nha vì mình đang âm điểm 

chúc pạn học giỏi

Ta có: \(A=\frac34\cdot\frac89\cdot\frac{15}{16}\cdot\frac{24}{25}\cdot\frac{35}{36}\cdot\frac{48}{49}\cdot\frac{63}{64}\)

\(=\frac{1\cdot3}{2\cdot2}\cdot\frac{2\cdot4}{3\cdot3}\cdot\frac{3\cdot5}{4\cdot4}\cdot\frac{4\cdot6}{5\cdot5}\cdot\frac{5\cdot7}{6\cdot6}\cdot\frac{6\cdot8}{7\cdot7}\cdot\frac{7\cdot9}{8\cdot8}\)

\(=\frac{1\cdot2\cdot\ldots\cdot7}{2\cdot3\cdot\ldots\cdot8}\cdot\frac{3\cdot4\cdot\ldots\cdot9}{2\cdot3\cdot\ldots\cdot8}=\frac18\cdot\frac92=\frac{9}{16}\)

a: \(=28\cdot100=2800\)

a, $-28\cdot41+100\cdot141+41\cdot(-72)$

$=41\cdot[(-28)+(-72)]+100\cdot141$

$=41\cdot(-100)+(-100)\cdot(-141)$

$=(-100)\cdot[41+(-141)]$

$=(-100)\cdot(-100)$

$=100\cdot100$

$=10000$

b, $35\cdot(65-6)-65\cdot(35+6)$

$=35\cdot65+35\cdot(-6)-65\cdot35-65\cdot6$

$=(35\cdot65-65\cdot35)+[35\cdot(-6)+65\cdot(-6)]$

$=0+(-6)\cdot(35+65)$

$=-6\cdot100$

$=-600$

c, $-48+48\cdot(-78)-21\cdot48$

$=-48\cdot1+(-48)\cdot78+(-48)\cdot21$

$=-48\cdot(1+78+21)$

$=-48\cdot(79+21)$

$=-48\cdot100$

$=-4800$

Bài làm :

\(a,35.34+35.38+65.75+65.45\)

\(=35.\left(34+38\right)+65.\left(74+45\right)\)

\(=35.72+65.120\)

\(=2520+780\)

\(=10320\)

\(b,39.8+60.2+21.8\)

\(=\left(39+21\right).8+60.2\)

\(=60.8+60.2\)

\(=60.\left(8+2\right)\)

\(=60.10=600\)

\(c,36.28+36.82+64.69+64.4\)

\(=36.\left(28+82\right)+64.\left(69+4\right)\)

\(=36.110+64.73\)

\(=3960+4672\)

\(=8632\)

\(d,123.1001\)

\(=123123\)

Học tốt