a) 4802 * 324 = 1555848

b) 3/5 *8/9 = 0.5333

c) 26.4 *7.8 = 205.92

d) 32.54 *2.05 = 66.7070

a ) 4082 x 324 = 1322568

b) 3/5 x 8/9 = 8/15

c) 26,4 x 7,8 = 20592

d) 32,54 x 2,05 =66, 707

Kết quả là 105/70 = 3/2

Chúc bn học tốt

a, 42x(54+17):71

=42x71:71=42

b, 123x(154-65):89

=123x89:89=123

c,324x(6+4):324

=324x10:324=10x324:324=10

\(a)\left(42\times54+17\times42\right):71\)

\(=42\times54+17\times42:71\)

\(=42\times\left(54+17\right):71\)

\(=42\times71:71\)

\(=42\)

\(b)\left(123\times154-65\times123\right):89\)

\(=123\times154-65\times123:89\)

\(=123\times\left(154-65\right):89\)

\(=123\times89:89\)

\(=123\)

\(c)\left(324\times6+4\times324\right):\left(162\times2\right)\)

\(=324\times6+4\times324:324\)

\(=324\times\left(6+4\right):324\)

\(=324\times10:324\)

\(=3240:324\)

\(=10\)

48,71 x 7,8 = 379.938

87,54 x 6,5 = 569.01

0,154 x 5,7 = 0.8778

121,7 x 8,6 = 1046.62

CHÚC HỌC TỐT !

a. 1⋅2⋅3+2⋅4⋅6+3⋅6⋅9+4⋅8⋅12

= 6+2⋅4⋅6+3⋅6⋅9+4⋅8⋅12

= 6+48+3⋅6⋅9+4⋅8⋅12

= 6+48+162+4⋅8⋅12

= 6+48+162+384

= 600

b . Ta có \(A=\frac{2010+2011}{2011+2012}=\frac{2010}{2011+2012}+\frac{2011}{2011+2012}.\)

Ta có : \(\frac{2010}{2011+2012}< \frac{2010}{2011}\) và \(\frac{2011}{2011+2012}< \frac{2011}{2012}\)

=> \(\frac{2010+2011}{2011+2012}< \frac{2010}{2011}+\frac{2011}{2012}\)

=> A < B

2,3 còn gọi dc là 2.30 cũng ko thay đổi giá trị nên x có thể là:

2.31

2.32

2.33

2.34

2.35

2.36

2.37

2.38

2.39

thỏa mãn đề bài

bạn ơi:2,31;

2,32

2,33;

Tính nhanh:    35 \(\times\) 119 \(\times\) 0,25 \(\times\) 100 \(\times\) ( 3: 0,4 - 7,5)

                    =  35 \(\times\) 119 \(\times\) 0,25 \(\times\) 100 \(\times\) ( 7,5 - 7,5)

                    =  35 \(\times\) 119 \(\times\) 0,25 \(\times\) 100 \(\times\) 0

                   = 0

(x+1)+(x+2)+...x+28=155

=> x + 1 + x + 2 + ... + x + 28 =155

=> 28x + (1 + 2 + 3 + ... + 28) =155

=> 28x + 28.(28+1):2 = 155

=> 28x + 406 = 155

=> 28x = 155 - 406 = -251

=> x = -251/28

Ta có:

(x+1)+(x+2)+...x+28=155

<=> x + 1 + x + 2 + ... + x + 28 =155

<=> 28x + (1 + 2 + 3 + ... + 28) =155

<=> 28x + 28.(28+1):2 = 155

<=> 28x + 406 = 155

<=> 28x = 155 - 406 = -251

=> x = \(-\frac{251}{28}\)

hok tốt

a. 

(1 + 3 + 5 + ... + 2007 + 2009 + 2011) x (125125 x 127 - 127127 x 125)

= (1 + 3 + 5 + ... + 2007 + 2009 + 2011) x 0

= 0

b.

\(\frac{2006\times125+1000}{126\times2006-1006}=\frac{2006\times125+1000}{125\times2006+1\times2006-1006}=\frac{2006\times125+1000}{125\times2006+1000}=1\)

a, 

( 1+3+5+7+…+2003+2005) x (125 125 x 127 – 127 127 x 125)

= ( 1+3+5+7+…+2003+2005) x (125 x 1001 x 127 – 127 x 1001x 125)

=  ( 1+3+5+7+…+2003+2005) x                   0  =    0