a. \(\frac{4}{25}\times72+\frac{4}{25}\times28=\frac{4}{25}\times\left(72+28\right)=\frac{4}{25}\times100=4\times4=16\)

b.\(0.5\times72+\frac{3}{6}\times28=0.5\times72+0.5\times28=0.5\times\left(72+28\right)=0.5\times100=50\)

a) 4/25 × 72 + 4/25 × 28

= 4/25 × (72+28)

= 4/25 × 100

= 16/100 × 100

= 16

b) 0.5 × 72 + 3/6 × 28

= 5/10 × 72 + 3/6 × 28

= 1/2 × 72 + 1/2 × 28

= 1/2 × (72 + 28)

= 1/2 × 100

= 5/10 × 100

= 50

làm đảo lại nhân = chia, trừ = cộng

0.5 +0.5 rồi chia 0.5 rồi - 0.5 rồi chia 0.5 mình sẽ ra được 3

dap an la 3 nhe 

violimpic lop 5 vong 8

baaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa là 3

88000đồng

88000 đồng

88000 đồng

\(0,4\times0,5\times64,2=12,84\)

0,4 x 0,5 x 64,2 = 12,84

0.4nhan0.5nhan64.2=12.84

\(122+\left(-22\right)+\left(-1\right)+25.4\)

\(=122-22-1+100\)

\(=199\)

`122+(-22)+(-1)+25xx4`

`=122-22-1+100`

`=100-1+100`

`=100+100-1`

`=200-1`

`=199`

=122+(-22)+(-1)+100

=122-22-1+100

=199

\(\Leftrightarrow20+8\left(x+3\right)=100\\ \Leftrightarrow8\left(x+3\right)=80\\ \Leftrightarrow x+3=10\\ \Leftrightarrow x=7\)

\(\left[516-\left(25\cdot4+16\right)\right]:8-68\)

\(=\dfrac{\left[516-100-16\right]}{8}-68\)

\(=\dfrac{400}{8}-68=50-68=-18\)

48x72+72x18+8x9x34

=48x72+72x18+(8x9)x34

=48x72+72x18+72x34

=72x(48+18+34)

=72x100

=7200

48 x 72 + 72 x 18 + 8 x 9 x 34

= 48 x 72 + 18 x 72 + 34 x 72

= ( 48 + 18 + 34 ) x 72

= 100 x 72

= 7200

48x72 + 72x18 + 8x9x34

= 48 x 72 +18x72 +x 72x34

= 72 x( 48+18+34)

= 72 x 100

= 7200