khong quy dong tu so hay so sanh
a 13/17 va 15/19
b 12/48 va 9/36
Khong quy dong mau so va tu so hay so sanh:
12/48 va 13/47
Viet ro cach giai giup mk nhe! Ai nhanh mk tk cho!
12/48 > 13/47
Đúng 100 % luôn .
Nhớ nhé !
Khong can quy dongmau so,hay so sanh cac phan so sau:
17/15 va 29/30
12/48 va 13/47
15/22 va 60/91
+ Ta có:
17/15 > 1; 29/30 < 1
=> 17/15 > 29/30
+ Ta có:
12/48 < 12/47 < 13/47
=> 12/48 < 13/47
+ 15/22 = 60/88 > 60/91
=> 15/22 > 60/91
Ko quy dong mau so va tu so hay so sanh:
12/48 va 13/47
Viet ro cach giai nhe!
gọi phân số trung gian là \(\frac{12}{47}\)
Ta có : \(\frac{12}{48}< \frac{12}{47}\); \(\frac{12}{47}< \frac{13}{47}\)
\(\Rightarrow\frac{12}{48}< \frac{12}{47}< \frac{13}{47}\)
\(\Rightarrow\frac{12}{48}< \frac{13}{47}\)
vậy \(\frac{12}{48}< \frac{12}{47}\)
Gọi phân số trung gian là: \(\frac{12}{47}\)
Ta có: \(\frac{12}{48}< \frac{12}{47};\frac{13}{47}>\frac{12}{47}\)
\(\Rightarrow\frac{12}{48}< \frac{13}{47}\)
khong quy dong tu so va mau so hay so sanh
a) 13/17 va 15/19
tim x biet
a) \(\frac{2}{3}\times x+\frac{3}{4}=3\)
b, 720:[41-(2x x-5)]=120
a)13/17 < 15/19
a) 2/3 x X + 3/4 = 3
2/3 x X = 3 - 3/4
2/3 x X = 9/4
X = 9/4 : 2/3
X = 27/8
a. Ta có : \(\frac{13}{17}=\frac{247}{323};\frac{15}{19}=\frac{255}{323}\)
Vì 255 > 247 nên 247/323 < 255/323
Hay \(\frac{13}{17}< \frac{15}{19}\)
b. \(\frac{2}{3}\times x+\frac{3}{4}=3\)
\(\frac{2}{3}\times x=3-\frac{3}{4}\)
\(\frac{2}{3}\times x=\frac{9}{4}\)
\(x=\frac{9}{4}:\frac{2}{3}\)
\(x=\frac{27}{8}\)
c. \(720:\left[41-\left(2\times x-5\right)\right]=120\)
\(\left[41-\left(2\times x-5\right)\right]=720:120\)
\(41-\left(2\times x-5\right)=6\)
\(2\times x-5=35\)
\(2\times x=40\)
\(x=20\)
a)\(\frac{13}{17}>\frac{15}{19}\)
b)\(720\div[41-(2x\times5)]=120\) c)\(\frac{2}{3}\times x+\frac{3}{4}=3\)
\(41-(2x\times5)=270\div120\) \(\frac{2}{3}\times x=3-\frac{3}{4}\)
\(41-(2x-5)=6\) \(\frac{2}{3}\times x=\frac{9}{4}\)
\(2x-5=41-6\) \(x=\frac{9}{4}\div\frac{2}{3}\)
\(2x-5=35\) \(x=\frac{9}{4}\times\frac{3}{2}\)
\(2x=35+5\) \(x=\frac{27}{8}\)
\(2x=40\)
\(x=40\div2\)
\(x=20\)
Khong quy dong mau so hay so sanh 2 phan so sau:12/13 va 13/14
Ta có :
\(\frac{12}{13}=1-\frac{1}{13}\)
\(\frac{13}{14}=1-\frac{1}{14}\)
Vì \(\frac{1}{13}>\frac{1}{14}\)nên \(1-\frac{1}{13}< 1-\frac{1}{14}\)
Vậy \(\frac{12}{13}< \frac{13}{14}\)
Ta thấy:
\(\frac{12}{13}=1-\frac{1}{13}\)
\(\frac{13}{14}=1-\frac{1}{14}\)
Vì 13<14.
=>\(\frac{1}{13}>\frac{1}{14}\)
=>\(1-\frac{1}{13}< 1-\frac{1}{14}\)
=>\(\frac{12}{13}< \frac{13}{14}\)
Vậy......
\(\frac{12}{13}\)và \(\frac{13}{14}\)
Ta có : \(\frac{12}{13}=\frac{12}{13}+\frac{1}{13}\) ; \(\frac{13}{14}=\frac{13}{14}+\frac{1}{14}\)
Ta thấy \(\frac{1}{13}>\frac{1}{14}\)=> \(\frac{12}{13}< \frac{13}{14}\)
so sanh 2 phan so khong quy dong tu so va mau so hay so sanh phan so \(\frac{23}{48}\)va \(\frac{47}{92}\)
So sánh không quy đồng thì:
\(\frac{23}{48}< \frac{47}{92}\)
k nha
23/48< 47/92
chúc bạn học tốt
So sánh hai p.số mà ko quy đồng:
\(\frac{23}{48}< \frac{47}{92}\)
Chúc học tốt
Khong quy dong mau so hay so sanh hai phan so 12 phan 49 va 13 phan 47
Vì \(\frac{12}{49}< \frac{13}{49}\)
\(\frac{13}{49}< \frac{13}{47}\)
Nên \(\frac{12}{49}< \frac{13}{47}\)
Ta có 13/47>13/49
Mà 13/49>12/49
=> 12/49<13/47
\(\frac{12}{49}\)và \(\frac{13}{47}\Rightarrow12.47\)và \(49.13\)\(\Rightarrow564\)và \(637\)
vì 564<637
nên \(\frac{12}{49}< \frac{13}{47}\)
khong quy dong , so sanh: \(\frac{12}{48}va\frac{9}{36}\)
Ta có:\(\frac{12}{48}=\frac{1}{4}\) \(\frac{9}{36}\)= \(\frac{1}{4}\)
Vì\(\frac{1}{4}=\frac{1}{4}\)nên \(\frac{12}{48}=\frac{9}{36}\)
Vậy \(\frac{12}{48}=\frac{9}{36}\)
khong quy dong mau so tu so hay so sANH CAC PHAN SO SAU
207/209va 209/211
101/100 va 103/101
79/65va 15/17
47/15 va 65/21
ban nao giai ca bai viet ca loi giai ra minh tick nhe