\(\dfrac{1111\times5}{1515\times7}=\dfrac{1111\times5}{303\times5\times7}=\dfrac{1111}{2121}\)

\(=\dfrac{11\times101}{21\times101}=\dfrac{11}{21}\)

32 x 50 / 48 x 75 = 1600 / 3600 = 4/9

63 x 81 / 135 x 84 = 5103 / 11340 = 9/20

1111 x 5 / 7 x 1515 = 5555 / 10605 = 11/21 

Chúc bạn học tốt !!!

32x50 / 48x75=1600/3600=4/9

63x81 /135x75=5103/10125=63/125

1111x5x1515x7=58 910 775

duyệt mình đi các bạn !

ã/9 

9/20

58910775

\(\frac{32\cdot50}{48\cdot75}=\frac{1600}{3600}=\frac{4}{9}\)

\(\frac{63\cdot81}{135\cdot84}=\frac{5103}{11340}=\frac{9}{20}\)

1111x5x1515x7=58910775

3⁴ ≡ 1 (mod 10)

⇒ 3⁴⁰ ≡ (3⁴)¹⁰ (mod 10) ≡ 1¹⁰ (mod 10) ≡ 1 (mod 10)

⇒ 7.3⁴⁰ ≡ 7.1 (mod 10) ≡ 7 (mod 10)

Vậy chữ số tận cùng của 7.3⁴⁰ là 7

121³ ≡ 1 (mod 10)

⇒ 121¹² ≡ (121³)⁴ (mod 10) ≡ 1⁴ (mod 10) ≡ 1 (mod 10)

125 ≡ 5 (mod 10)

125³ ≡ 5 (mod 10)

⇒ 125¹² ≡ (125³)⁴ (mod 10) ≡ 5⁴ (mod 10) ≡ 5 (mod 10)

⇒ 125¹³ ≡ 125.125¹² (mod 10) ≡ 5.5 (mod 10) ≡ 5 (mod 10)

⇒ 121¹² + 125¹³ ≡ 1 + 5 (mod 10) ≡ 6 (mod 10)

Vậy chữ số tận cùng của 121¹² + 125¹³ là 6

10¹⁰ ≡ 0 (mod 10)

11¹¹ ≡ 1 (mod 10)

15¹⁵ ≡ 5 (mod 10)

16⁴ ≡ 6 (mod 10)

⇒ 16¹⁶ ≡ (16⁴)⁴ (mod 10) ≡ 6⁴ (mod 10) ≡ 6 (mod 10)

⇒ 10¹⁰ + 11¹¹ + 15¹⁵ + 16¹⁶ ≡ 0 + 1 + 5 + 6 (mod 10) ≡ 2 (mod 10)

Vậy chữ số tận cùng của 10¹⁰ + 11¹¹ + 15¹⁵ + 16¹⁶ là 2

=11/15x7/5=77/75

37/11 = 37/11

3737/111111 = 101/3003

1111/1515 = 11/15

85/125 = 17/25

114/246 = 19/41

2002 x 3003 + 4004/2005 x 2004 - 4010 = 4010006 + 4002,002993 - 4010 = 4009998,003

nhà mik chưa có hok phẩy nha

\(\frac{2323+1313+1414+1515+1616}{4141+2222+2323+2424+2525}\)

=\(\frac{8181}{13635}\)

18180,8               

\(\dfrac{1111}{1212}\)  và  \(\dfrac{1515}{1616}\)

\(\dfrac{1111}{1212}=\dfrac{1111\times1616}{1212\times1616}=\dfrac{1795376}{1958592}\)

\(\dfrac{1515}{1616}=\dfrac{1515\times1212}{1616\times1212}=\dfrac{1836180}{1958592}\)

Vì: 1836180 > 1795376

=> \(\dfrac{1111}{1212}< \dfrac{1515}{1616}\)

\(\dfrac{1111}{1212}\) = \(\dfrac{1111:101}{1212:101}\) = \(\dfrac{11}{12}\)= 1 - \(\dfrac{1}{12}\) ;    \(\dfrac{1515}{1616}\) =\(\dfrac{1515:101}{1616:101}\) = \(\dfrac{15}{16}\) = 1 -\(\dfrac{1}{16}\)

Vì \(\dfrac{1}{12}\) > \(\dfrac{1}{16}\) nên  \(\dfrac{1111}{1212}\) < \(\dfrac{1515}{1616}\)

\(\dfrac{1111}{1212}=\dfrac{11}{12}=1-\dfrac{1}{12}\)

\(\dfrac{1516}{1516}=\dfrac{15}{16}=1-\dfrac{1}{16}\)

Vì: \(\dfrac{1}{12}>\dfrac{1}{16}\) nên \(1-\dfrac{1}{12}< 1-\dfrac{1}{16}\)

Vậy\(\dfrac{1111}{1212}< \dfrac{1515}{1616}\)

1111.5/1515.7=101.11.5/101.5.3.7=11/3.7=11/21