`a)2018xx(1/2+1212/2424)`

`=2018xx(1/2+1/2)`

`=2018xx2/2=2018`

______________________________

`b)15xx2121/4343+15xx222222/434343`

`=15xx(2121/4343+222222/434343)`

`=15xx(21/43+22/43)`

`=15xx43/43=15`

a.2018x1=2018

b.15x(21/43+22/43)=15x1=15

A)2018

B)15

\(2018\times\left(\frac{1}{2}+\frac{1212}{2424}\right)=2018\times\left(\frac{1}{2}+\frac{12}{24}\right).\)

                                                  \(=2018\times\left(\frac{1}{2}+\frac{1}{2}\right)\)

                                                  \(=2018\times1=2018\)

2018.(1/2+1212/2424)

=2018.(1/2+1/2)

=2018.2/2

=2018.1

=2018

Hk tốt

\(2018\times\left(\frac{1}{2}+\frac{1212}{2424}\right)\)

\(=2018\times\left(\frac{1}{2}+\frac{1}{2}\right)\)

\(=2018\times1=2018\)

~ Hok tốt ~

Ta có:

  \(\frac{1212}{2424}=\frac{1}{2}\)

\(\Rightarrow2018.\left(\frac{1}{2}+\frac{1}{2}\right)=2018.1=2018\)

chia 101/101 để ra được 1/2

\(2018.\frac{1212}{2424}=2018.\frac{1212:1212}{2424:1212}=2018.\frac{1}{2}=1009\)

~Study well~

#ARMY_BLINK#

Trả lời:

2018 * ( 1212/2424 )

= 2018 * 1/2

= 1009

~~GOD~~

\(2018x\frac{1212}{2424}=2018x\frac{1212:1212}{2424:2424}=2018x\frac{1}{2}=1009\)

MAGCIEPCNIL

HÃY LUÔN ;-)

a)Ta có : \(\dfrac{1212}{1414}=\dfrac{12.101}{14.101}=\dfrac{12}{14}\)

\(\dfrac{121212}{242424}=\dfrac{12.10101}{24.10101}=\dfrac{12}{24}\)

Vậy \(\dfrac{12}{24}=\dfrac{1212}{2424}=\dfrac{121212}{242424}\)

Ta có : \(\dfrac{2424}{3535}=\dfrac{24.101}{35.101}=\dfrac{24}{35}\)

\(\dfrac{242424}{353535}=\dfrac{24.10101}{35.10101}=\dfrac{24}{35}\)

Vậy \(\dfrac{24}{35}=\dfrac{2424}{3535}=\dfrac{242424}{353535}\)

Ta có : \(\dfrac{224466}{255075}=\dfrac{22.10203}{25.10203}=\dfrac{22}{25}\)

Vậy \(\dfrac{22}{25}=\dfrac{224466}{255075}\)

Trả lời:

\(2018\times\left(\frac{1212}{1212}\div\frac{2424}{2424}\right)\)

\(=2018\times\left(1\div1\right)\)

\(=2018\times1\)

\(=2018\)

Tính nhanh

\(2018\times\left\{\frac{1212}{1212}\div\frac{2424}{2424}\right\}\)

\(=2018\times1\)

\(=2018\)

2018×(1212/1212×2424/2424)

2018×1

2018

a, \(\dfrac{3}{5}\) \(\times\) \(\dfrac{6}{7}\) + \(\dfrac{3}{5}\) : 7 + \(\dfrac{6}{5}\)

= \(\dfrac{3}{5}\) \(\times\) \(\dfrac{6}{7}\) + \(\dfrac{3}{5}\) \(\times\) \(\dfrac{1}{7}\) + \(\dfrac{6}{5}\)

= \(\dfrac{3}{5}\) \(\times\) ( \(\dfrac{6}{7}\) + \(\dfrac{1}{7}\)) + \(\dfrac{6}{5}\)

= \(\dfrac{3}{5}\) + \(\dfrac{6}{5}\)

= \(\dfrac{9}{5}\) 

b, 2018 \(\times\) ( \(\dfrac{1}{2}\) + \(\dfrac{1212}{2424}\))

= 2018 \(\times\) ( \(\dfrac{1}{2}\) + \(\dfrac{1}{2}\))

= 2018 \(\times\)1

= 2018

a) 3/5 x 6/7 + 3/5 x 1/7 + 6/5

3/5 x ( 6/7 + 1/7 ) + 6/5

3/5 x 7/7 + 6/5 

3/5 x 1 + 6/5

3/5 + 6/5 

9/5

b) 2018 x ( 1/2 + 1212/ 2424 )

2018 x ( 1/2 + 12/24 )

2018 x ( 1/2 + 1/2 )

2018 x 2/2

2018 x 1

2018

Học tốt

\(\dfrac{1212}{1515}+\dfrac{1212}{3535}+\dfrac{1212}{6363}+\dfrac{1212}{9999}\)

=\(\dfrac{12}{15}+\dfrac{12}{35}+\dfrac{12}{63}+\dfrac{12}{99}\)

=\(\dfrac{16}{11}\)

Giải:

\(\dfrac{1212}{1515}+\dfrac{1212}{3535}+\dfrac{1212}{6363}+\dfrac{1212}{9999}\) 

\(=\dfrac{12}{15}+\dfrac{12}{35}+\dfrac{12}{63}+\dfrac{12}{99}\) 

\(=12.\left(\dfrac{1}{3.5}+\dfrac{1}{5.7}+\dfrac{1}{7.9}+\dfrac{1}{9.11}\right)\) 

\(=12.\dfrac{1}{2}.\left(\dfrac{2}{3.5}+\dfrac{2}{5.7}+\dfrac{2}{7.9}+\dfrac{2}{9.11}\right)\) 

\(=6.\left(\dfrac{1}{3}-\dfrac{1}{5}+\dfrac{1}{5}-\dfrac{1}{7}+\dfrac{1}{7}-\dfrac{1}{9}+\dfrac{1}{9}-\dfrac{1}{11}\right)\) 

\(=6.\left(\dfrac{1}{3}-\dfrac{1}{11}\right)\) 

\(=6.\dfrac{8}{33}\) 

\(=\dfrac{16}{11}\)

\(=\dfrac{12}{15}+\dfrac{12}{35}+\dfrac{12}{63}+\dfrac{12}{99}=12\cdot\left[\dfrac{1}{15}+\dfrac{1}{35}+\dfrac{1}{63}+\dfrac{1}{99}\right]=12\cdot\left[\dfrac{1}{3\cdot5}+\dfrac{1}{5\cdot7}+\dfrac{1}{7\cdot9}+\dfrac{1}{9\cdot11}\right]=12\cdot\dfrac{1}{2}\cdot\left[\dfrac{1}{3}-\dfrac{1}{5}+\dfrac{1}{5}-\dfrac{1}{7}+\dfrac{1}{7}-\dfrac{1}{9}+\dfrac{1}{9}-\dfrac{1}{11}\right]=6\cdot\left[\dfrac{1}{3}-\dfrac{1}{11}\right]=6\cdot\dfrac{8}{33}=\dfrac{48}{33}=\dfrac{16}{11}\)