a) Các phân số tối giản:

\(\frac{1}{5}\text{ };\text{ }\frac{17}{20}\)

b) Rút gọn:

\(\frac{12}{18}=\frac{12\div6}{18\div6}=\frac{2}{3}\)

\(\frac{15}{95}=\frac{15\div5}{95\div5}=\frac{3}{19}\)

a) \(\frac{1}{5}\);\(\frac{17}{20}\)

b) \(\frac{12}{18}\)= \(\frac{2}{3}\);\(\frac{15}{95}\)= \(\frac{3}{19}\)

Hello. My name is Duc. Let me introduce myself and my family. I'm 18 this year, a student of a school television. Walking and playing with friends is my hobby. I was born and raised in the province HB. My family has 4 people: parents, my, my sister and me. My father is an engineer. My mother was a doctor. 9 years old and my brother is studying in an elementary school. She studied very hard and is one of the best student in her class. On good days, and with spare time, my family often went on to play with grandparents, it is very meaningful and fun. I feel very happy to be alive in this family. 
I love my family very much. I will try to learn and do well to take care of my family. I hope that my family is happy and there is always the best thing. 
Thank you for listening to my thoughts. 
Wishing you a happy day.

HI! I come from a family of five people: my parents, my two younger brother and I. 
My parents are farmers who work very hard in the field. On the trip, they are so busy. Inspite of its, they always take more time as possible to take care of us. My father is great father. Dad always teachs me things to do and not to do in this life. He is also good husband for may mom. On the trip, he often helps my mom to cook some special dishes. And at weekend, he usually fixes everything broken in our house. 
About my mother. she is a caring woman. mom is always the first person to get up early in the morning to wake up I and my first younger brother and prepare breakfast before going to school. She is very thoughful! About my two younger brothers. the first one is 16 years old and the second one is 6 years old. they are obedient! And I, I'm in final hingh school and in my attempt. I'm under a lot of study pressure. inspite of its, I always dream and try to study harder and harder to get success in the future.
It's my family. I feel very happy in it. And I love my family more than anything! 

Đ/A đây:

=\(\frac{2^{15}.3^5-2^{12}.3^6}{2^{12}.3^6+2^{12}.3^5}\)

=\(\frac{2^{12}.3^5.\left(2^3-3\right)}{2^{12}.3^5.\left(3+1\right)}\)

                                               cố lên

=\(\frac{5}{4}\)

Giúp mình bài 1 ,2,3,4, 5 , 6, 7 ,8 ạ

143/132=13/12

3535/3737=35/37

~HT~

K cho mình nha mình đang cần tăng SP CẢM ƠN MỌI NHƯỜI

@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@

\(\frac{143}{132}=\frac{143:11}{132:11}=\frac{13}{12};\frac{3535}{3737}=\frac{3535:101}{3737:101}=\frac{35}{37}\)

Ta có: 17+a/35=5/7

Quy đồng mẫu số phân số 5/7 được:

17+a/35=5*5/7*5

17+a/35=25/35

Ta thấy: 17+a =35

a=25-17

a=8 

Vậy số đó là 8.

   Ps: nhớ k

                                                                                                                                                            # Aeri # 

a,3535/3737-x=2121/7474

35/37-x=21/74

x=35/37-21/74

x=49/74

b,x/1968-217/984=187/492

x/1968=187/492+217/984

x/1968=197/328

x=197.1967/328

x=????

\(\frac{3535}{3737}-x=\frac{2121}{7474}\)

                 \(x=\frac{3535}{3737}-\frac{2121}{7474}\)

                 \(x=\frac{7070}{7474}-\frac{2121}{7474}\)

a)3535/3737-x=2121/7474

x=3535/3737-2121/7474

x=49/74

b)x:1968-217/984=187/492

x:1968=187/492+217/984

x:1968=197/328

x=197/328x1968

x=1182

tick nha bạn

Đặt \(A=\frac{1}{5}+\frac{1}{5^3}+...+\frac{1}{5^{101}}\)

\(\Rightarrow25A=5+\frac{1}{5}+\frac{1}{5^3}+...+\frac{1}{5^{99}}\)

\(\Rightarrow25A-A=\left(5+\frac{1}{5}+\frac{1}{5^3}+...+\frac{1}{5^{99}}\right)-\left(\frac{1}{5}+\frac{1}{5^3}+\frac{1}{5^5}+...+\frac{1}{5^{101}}\right)\)

hay \(24A=5-\frac{1}{5^{101}}\)

\(\Rightarrow A=\frac{5-\frac{1}{5^{101}}}{24}\)

\(\Rightarrow A:\left(1-\frac{1}{5^{102}}\right)=\frac{5-\frac{1}{5^{101}}}{24}.\frac{1}{1-\frac{1}{5^{102}}}\)

\(=\frac{5\left(1-\frac{1}{5^{102}}\right)}{24}.\frac{1}{1-\frac{1}{5^{102}}}=\frac{5}{24}\)