18 + 16 : 8                XVIII + XVI: VIII

= 18 + 2                    XVIII + II

= 20                         XX

XVIII + XVI : VIII

= 18 + 16 : 8

= 18 : 2

= 9.

\(\dfrac{25}{11}.\dfrac{13}{12}.\left(-2,2\right)\)

\(=\dfrac{25}{11}.\left(-2,2\right).\dfrac{13}{12}\)

\(=\dfrac{25}{11}.\dfrac{-11}{5}.\dfrac{13}{12}\)

\(=-5.\dfrac{13}{12}\)

\(=\dfrac{-65}{12}\)

\(\left(\dfrac{3}{4}+\dfrac{1}{4}\right):x=\dfrac{25}{4}\)

\(1:x=\dfrac{25}{4}\)

\(x=1:\dfrac{25}{4}=1.\dfrac{4}{25}\)

\(x=\dfrac{4}{25}\)

( 3/4 + 1/4 ) : x = 25/4 

⇒ 1 : x = 25/4

⇒  x = 4/25.

Vậy x = 4/25.

Vì 14/14 = 1; 15/15 = 1 ; ....

⇔ Tổng trên là 6 < 11.

Vì 20/20 = 1 ; 21/21 = 1 ; ...

⇒ Tổng trên là 6 < 15.

Vlll là số 8 ( trong số La Mã )

Là số 8 nhé

A = \(\dfrac{1414+1515+1616+1717+1818+1919}{2020+2121+2022+2323+2424+2525}\)

A = \(\dfrac{101\times\left(14+15+16+17+18+19\right)}{101\times\left(20+21+22+23+24+25\right)}\)

A = \(\dfrac{99}{135}\) 

A = \(\dfrac{11}{15}\)

a = \(\dfrac{1}{2}\)b + c = 34 \(\times\) \(\dfrac{1}{2}\) + 56 + 56 \(\times\) 300 = 16873

A = 34 \(\times\) 23 \(\times\) 16873 + 34 \(\times\) 34 + 56 + 56 \(\times\) 300

A = 13194686 + 1156 +  56 + 16800

A = 13212698

\(A=\dfrac{2}{3}+\dfrac{3}{4}.\left(\dfrac{-4}{9}\right)\)

\(A=\dfrac{2}{3}+\dfrac{-1}{3}\)

\(A=\dfrac{1}{3}\)

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( *Xem lại câu B nha bạn )

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\(C=\left(\dfrac{3}{4}-0,2\right).\left(0,4-\dfrac{4}{5}\right)\)

\(C=\left(\dfrac{3}{4}-\dfrac{1}{5}\right).\left(\dfrac{2}{5}-\dfrac{4}{5}\right)\)

\(C=\dfrac{11}{20}.\dfrac{-2}{5}\)

\(C=\dfrac{-11}{50}\)