36 của \(\dfrac{4}{9}\)
\(\dfrac{......}{9}=\dfrac{4}{36}\)
A, 1 b, 4 c, 9 d,36
hoàn thành các phép tính sau
a) tính tổng \(2\dfrac{3}{4}\) +\(5\dfrac{7}{9}\)
cách 1
\(2\dfrac{3}{4}+5\dfrac{7}{9}=\dfrac{...}{4}+\dfrac{...}{9}\)
\(=\dfrac{99}{36}+\dfrac{...}{36}\)
\(=\dfrac{...}{36}=...\)
cách 2
\(2\dfrac{3}{4}+5\dfrac{7}{9}=2\dfrac{...}{36}+5\dfrac{...}{36}\)
=\(7\dfrac{...}{36}=8\dfrac{...}{36}\)
Cách 1
\(2\dfrac{3}{4}\)+ \(5\dfrac{7}{9}\)= \(\dfrac{11}{4}+\dfrac{47}{9}\)
= \(\dfrac{99}{36}+\dfrac{188}{36}\)
= \(\dfrac{287}{36}\)= 7,9722...
Cách 2
\(2\dfrac{3}{4}+5\dfrac{7}{8}=2\dfrac{55}{36}+5\dfrac{55}{36}\)
= \(7\dfrac{55}{36}=8\dfrac{19}{36}\)
Cách 1 mình làm nhầm bài đúng phải là
\(2\dfrac{3}{4}+5\dfrac{7}{9}=\dfrac{11}{4}+\dfrac{52}{9}=\dfrac{99}{36}+\dfrac{208}{36}\)
=\(\dfrac{307}{36}\)=8,527777778
\(\dfrac{-7}{9}+\dfrac{-2}{9}\)
\(\dfrac{15}{4}-\dfrac{-3}{4}\)
\(\dfrac{1}{6}-\dfrac{1}{36}\)
\(1-\dfrac{3}{2}\)
\(2-\dfrac{4}{5}\)
\(\dfrac{-7}{9}+\dfrac{-2}{9}=\dfrac{-9}{9}=-1\)
\(\dfrac{15}{4}-\dfrac{-3}{4}=\dfrac{18}{4}=\dfrac{9}{2}\)
\(\dfrac{1}{6}-\dfrac{1}{36}=\dfrac{6}{36}-\dfrac{1}{36}=\dfrac{5}{36}\)
\(1-\dfrac{3}{2}=\dfrac{2}{2}-\dfrac{3}{2}=\dfrac{-1}{2}\)
\(2-\dfrac{4}{5}=\dfrac{10}{5}-\dfrac{4}{5}=\dfrac{6}{5}\)
Trong một dãy tính chỉ có phép cộng và phép trừ phân số, ta thực hiện phép tính theo thứ tự từ trái sang phải :
Tính :
\(\dfrac{2}{9}+\dfrac{5}{-12}-\dfrac{-3}{4}\)
Điền số thích hợp vào chỗ trống để hoàn thành phép tính :
\(\dfrac{2}{9}+\dfrac{5}{-12}-\dfrac{-3}{4}=\dfrac{2}{9}+\dfrac{-5}{12}+\dfrac{3}{4}=\dfrac{2.4}{36}+\dfrac{\left(-5\right).....}{36}+\dfrac{3......}{36}=\dfrac{8-....+.....}{36}=\dfrac{20}{36}=\dfrac{....}{....}\)
Số?
a) \(\dfrac{2}{5}=\dfrac{2\times?}{5\times?}=\dfrac{10}{25}\) \(\dfrac{4}{7}=\dfrac{4\times2}{7\times?}=\dfrac{?}{?}\)
b) \(\dfrac{36}{40}=\dfrac{36:?}{40:?}=\dfrac{9}{10}\) \(\dfrac{24}{32}=\dfrac{24:?}{32:8}=\dfrac{?}{?}\)
a) \(\dfrac{2}{5}=\dfrac{2\times5}{5\times2}=\dfrac{10}{25}\)
\(\dfrac{4}{7}=\dfrac{4\times2}{7\times2}=\dfrac{8}{14}\)
b) \(\dfrac{36}{40}=\dfrac{36:4}{40:4}=\dfrac{9}{10}\)
\(\dfrac{24}{32}=\dfrac{24:8}{32:8}=\dfrac{3}{4}\)
\(\dfrac{4}{9}+\dfrac{16}{36}\)
\(=\dfrac{4}{9}+\dfrac{4}{9}=\dfrac{8}{9}\)
\(x+\dfrac{4}{9}+\dfrac{8}{18}+\dfrac{12}{27}+\dfrac{16}{36}=\dfrac{16}{9}\)
giúp mk với ạ
x + 4/9 + 8/18 + 12/27 + 16/36 = 16/9
x + (4/9+12/27)+(8/12+16/36) = 16/9
x + 8/9 + 10/9 = 16/9
x + 2 = 16/9
x = 16/9 - 2
x = -2/18
x+4/9+4/9+4/9+4/9=16/9
x+4/9.4=16/9
x+16/9=16/9
--> x = 0
\(a,\dfrac{9}{12}=\dfrac{3}{...}=\dfrac{...}{36}\\ b,\dfrac{4}{6}=\dfrac{10}{...}=\dfrac{...}{3}\)
a.\(\dfrac{9}{12}=\dfrac{3}{4}=\dfrac{27}{36}\)
b.\(\dfrac{4}{6}=\dfrac{10}{15}=\dfrac{2}{3}\)
\(\dfrac{9}{12}=\dfrac{3}{4}=\dfrac{27}{36}\)
\(\dfrac{4}{6}=\dfrac{10}{15}=\dfrac{2}{3}\)
Tính (Tính hợp lí nếu có thể)
a) \(\dfrac{-7}{12}\)-\(\dfrac{3}{36}\)
b) (4-\(\dfrac{5}{12}\)):2+\(\dfrac{5}{24}\)
c) \(\dfrac{8}{9}\)+\(\dfrac{1}{9}\).\(\dfrac{2}{13}\)+\(\dfrac{1}{9}\).\(\dfrac{11}{13}\)
d) \(\dfrac{3}{4}\).\(\dfrac{8}{9}\).\(\dfrac{15}{16}\). ... .\(\dfrac{9999}{10000}\)
e) \(\dfrac{3}{1.4}\)+\(\dfrac{3}{4.7}\)+\(\dfrac{3}{7.10}\)+...+\(\dfrac{3}{97.100}\)
*Lưu ý: Mong các anh chị trình bày chi tiết để em có thể hiểu bài, em xin các anh chị đừng viết mỗi kết quả xong em chả biết một cái gì ;-;
a: =-21/36-3/36=-24/36=-2/3
b: =43/12*1/2+5/24=43/24+5/24=2
c: =8/9+1/9=1
e: =1-1/4+1/4-1/7+...+1/97-1/100
=1-1/100=99/100