Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
rút gọn phân số :
4/5+21/15=4/5+7/5=11/5
8/9-25/45=8/9-5/9=3/9
tính :
5/6+2/7+15/6=5/6+15/6+2/7
=10/3+2/7=76/21
7/8-9/6.7/8=7/8-21/16=-7/16
chúc bạn học tốt !!!
1.
\(\frac{5}{3}-\frac{1}{4}+\frac{1}{3}-\frac{3}{4}\)
\(=\left(\frac{5}{3}+\frac{1}{3}\right)-\left(\frac{1}{4}+\frac{3}{4}\right)\)
\(=2-1=1\)
\(\frac{2}{7}\cdot\frac{1}{5}+\frac{2}{7}\cdot\frac{4}{5}=\frac{2}{7}\cdot\left(\frac{1}{5}+\frac{4}{5}\right)=\frac{2}{7}\cdot1=\frac{2}{7}\)
#Louis
\(1.a)\frac{5}{3}-\frac{1}{4}+\frac{1}{3}-\frac{3}{4}\)
\(=\left(\frac{5}{3}+\frac{1}{3}\right)-\left(\frac{1}{4}+\frac{3}{4}\right)\)
\(=2-1\)
\(=1\)
\(b)\frac{2}{7}\times\frac{1}{5}+\frac{2}{7}\times\frac{4}{5}\)
\(=\frac{2}{7}\times\left(\frac{1}{5}+\frac{4}{5}\right)\)
\(=\frac{2}{7}\times1\)
\(=\frac{2}{7}\)
\(2.a)\frac{5}{6}+\frac{7}{12}-\frac{2}{9}\)
\(=\frac{30}{36}+\frac{21}{36}-\frac{8}{36}\)
\(=\frac{43}{36}\)
\(b)\frac{4}{9}\times\frac{5}{8}+\frac{1}{6}\)
\(=\frac{5}{18}+\frac{1}{6}=\frac{5}{18}+\frac{3}{18}\)
\(=\frac{8}{18}=\frac{4}{9}\)
\(c)2:\frac{3}{11}-\frac{13}{12}\)
\(=2\times\frac{11}{3}-\frac{13}{12}\)
\(=\frac{22}{3}-\frac{13}{12}\)
\(=\frac{25}{4}\)
b, 3/5 + 4/7 + 2/8 + 10/25 + 9/21 + 28/16
= 3/5 + 4/7 + 2/8 + 2/5 + 3/7 + 14/8
= (3/5 + 2/5) + ( 4/7 + 3/7) + ( 2/8 + 14/8)
= 1 + 1 + 7/4
= 2 + 7/4 = 15/4
c , 8/7 + 7/6 + 5/8 + 10/12 + 24/28 + 6/16
= c , 8/7 + 7/6 + 5/8 + 5/6 + 6/7 + 1/2
= (8/7 + 6/7) + (7/6 + 5/6) + 5/8 + 1/2
= 14/7 + 12/6 + 5/8 + 1/2
= 2 + 2 + 5/8 + 1/2
= 4 + 9/8 = 41/8
2/3 : 1/2 + 1/3 : 1/2
= 4/3 + 2/3
= 2
3/5 : 4/7 : 7/6
= 21/20 : 7/6
= 9/10
4/9 x 7/5 : 7/9
= 28/45 : 7/9
= 4/5
Em nhớ k anh nha
có thể tính nốt phép tính 3/4 x 3/2 + 3/4 x 1/2 có đc ko ạ
TL :
1 + 1 + 2 + 2 + 3 + 3 + 4 + 4 + 5 + 5 + 6 + 6 + 7 + 7 + 8 + 8 + 9 + 9 = 90
HT
a) \(x-\frac{4}{9}=\frac{5}{6}\)
\(\Leftrightarrow\frac{18x}{18}-\frac{8}{18}=\frac{15}{18}\)
\(\Rightarrow18x-8=15\)
\(\Leftrightarrow18x=15+8\)
\(\Leftrightarrow18x=23\)
\(\Leftrightarrow x=\frac{23}{18}\)
Vậy \(x=\frac{23}{18}\)
b)\(x-7=\frac{1}{6}\)
\(\Leftrightarrow\frac{6x}{6}-\frac{42}{6}=\frac{1}{6}\)
\(\Rightarrow6x-42=1\)
\(\Leftrightarrow6x=42+1\)
\(\Leftrightarrow6x=43\)
\(\Leftrightarrow x=\frac{43}{6}\)
Vậy \(x=\frac{43}{6}\)
c)\(x-\frac{7}{8}=11\)
\(\Leftrightarrow\frac{8x}{8}-\frac{7}{8}=\frac{88}{8}\)
\(\Rightarrow8x-7=88\)
\(\Leftrightarrow8x=88+7\)
\(\Leftrightarrow8x=95\)
\(\Leftrightarrow x=\frac{95}{8}\)
Vậy \(x=\frac{95}{8}\)
#bn cs thể bỏ\(\Leftrightarrow;\Rightarrow\)đều đc nhé #
#hoktot<3#
a, x - 4/9 = 5/6
x = 5/6 + 4/9
x = 69/54
b, x - 7 = 1/6
x = 1/6 + 7
x = 43/6
c, x - 7/8 = 11
x = 11 + 7/8
x = 95/8
Bài 1:
a, \(\frac{1}{7}+3+\frac{5}{6}=\frac{1}{7}+\frac{3}{1}+\frac{5}{6}=\frac{6}{42}+\frac{126}{42}+\frac{35}{42}=\frac{167}{42}\)
b, \(\frac{4}{7}+\frac{5}{9}+4=\frac{4}{7}+\frac{5}{9}+\frac{4}{1}=\frac{36}{63}+\frac{35}{63}+\frac{252}{63}=\frac{323}{63}\)
Lời giải:
$\frac{7}{9}\times \frac{5}{6}=\frac{7\times 5}{9\times 6}=\frac{35}{54}$