a: \(\dfrac{31995-81}{42660-108}=\dfrac{31914}{42552}=\dfrac{3}{4}\)

b: \(\dfrac{3\cdot5\cdot7\cdot11\cdot13\cdot37-10101}{1212120+40404}=\dfrac{545454}{1252524}=\dfrac{27}{62}\)

a, $\frac{31995-81}{42660-108}$

= $\frac{395.81-81}{395.108-108}$

=$\frac{81.394}{394.108}$

= $\frac{81}{108}$          = $\frac{3}{4}$

b, $\frac{3.5.7.11.13.37-10101}{1212120+40404}$

= $\frac{3.5.7.11.13.37-3.7.13.37}{\mathrm{3.7.12.13.37.10}+\mathrm{3.4.7.13.37}}$

= $\frac{\left(\mathrm{3.7.13.37}\right)(5.11-1)}{\left(\mathrm{3.7.13.37}\right)(120+4)}$

= $\frac{5.11-1}{120+4}$

= $\frac{54}{124}$ = $\frac{27}{62}$

A = \(\frac{3^4\left(5.79-1\right)}{2^2.3^2\left(5.79-1\right)}=\frac{9}{4}\); B = \(\frac{3.7.13.37\left(5.11-1\right)}{4.3.7.13.37\left(3.5-1\right)}=\frac{54}{4.14}=\frac{2.9}{4.2.7}=\frac{9}{28}\)

\(\frac{31995-81}{42660-108}=\frac{3}{4}\)

\(\frac{31995-81}{42660-108}\)

\(=\frac{31914}{42554}\)

\(=\frac{3}{4}\)

Vậy ...........................................

\(=\frac{3}{4}\)

27/62

\(\frac{3.5.7.11.13.37-10101}{1212120+40404}\)

\(=\frac{3.5.7.11.13.37-3.7.13.37}{40404.30+40404.1}\)

\(=\frac{3.7.13.37.\left(5.11-1\right)}{40404.\left(30+1\right)}\)

\(=\frac{3.7.13.37.54}{40404.31}\)

\(=\frac{3.7.13.37.54}{3.7.13.37.31.4}\)

\(=\frac{54}{31.4}=\frac{27}{62}\)

31995 - 81 / 42660 - 108 

= 31914 / 42552 

= 3.10638 / 4.10638 

= 3/4

=3/4

tk mk nha 

31995 - 81 / 42660 - 108 
= 31914 / 42552 
= 3.10638 / 4.10638 
= 3/4

:3

ra số thập phân: 31886,99787

\(=\frac{3\text{x}5x7x11\text{x}13\text{x}37-3\text{x}7\text{x}13\text{x}37}{2^3x3^2x5\text{x}7\text{x}13\text{x}37+2^2x3\text{x}7\text{x}13\text{x}37}=\frac{3\text{x}7\text{x}13\text{x}37\left(5\text{x}11-1\right)}{2^2x3\text{x}7\text{x}13\text{x}37\left(2\text{x}3\text{x}5+1\right)}\)

\(=\frac{54}{2^2x31}=\frac{54}{124}=\frac{27}{62}\) thử lại kết quả rồi nhé

27/62

gà🦃

5.7.11.13.37-10101/1212120+40404

=3.5.7.11.13.37-10101/1212120.1/10+40404 (vì 1/1212120=1/121212.1/10)

= 3.37.7.11.13.5-101010/121212.1/100+40404

=111.1001.5-5/6.1/100+40404

=151515.5-250/3

=595959-250/3

=1787876/3