Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
a, \(\frac{5}{11}\times\frac{7}{25}+\frac{15}{11}\times\frac{1}{5}\)
\(=\frac{5}{11}\times\frac{7}{25}+\frac{5}{11}\times\frac{3}{5}\)
\(=\frac{5}{11}\times\left(\frac{7}{25}+\frac{3}{5}\right)\)
\(=\frac{5}{11}\times\frac{22}{25}\)
\(=\frac{2}{5}\)
b, \(\frac{3}{7}\times\frac{25}{19}-\frac{1}{7}\times\frac{18}{19}\)
\(=\frac{1}{7}\times\frac{75}{19}-\frac{1}{7}\times\frac{18}{19}\)
\(=\frac{1}{7}\times\left(\frac{75}{19}-\frac{18}{19}\right)\)
\(=\frac{1}{7}\times3\)
\(=\frac{3}{7}\)
1)A=aaa xb =ax1111xb =axbbbb =B
2) (1+4+7+.....+100):x =17
( (100+1)x34:2):x =17
=> 101x17:x =17
=>17x x=101x x
=> x =101
\(\frac{5}{7}\)<\(\frac{15}{12}\)
\(\frac{17}{21}\)<\(\frac{17}{19}\)
\(\frac{9}{11}\)< \(\frac{13}{15}\)
\(\frac{19}{15}\)< \(\frac{15}{11}\)
Giữ nguyên A = abc + 365
B = (a . 100 + 60 + c) + (300 + b . 10 + 4)
B = a . 100 + 60 + c + 300 + b . 10 + 4
B = abc + 364
Vì 365 > 364 nên A > B
14/15:7/5-8/15
=14/15x5/7-8/15
=2/3-8/15
=10/15-8/15
=2/15
Chọn A nha bạn
a )
Ta có :
\(A=18\times19=\left(17+1\right)\times19=17\times19+19\)
\(B=17\times20=17\times\left(19+1\right)=17\times19+17\)
Do \(17\times19+19>17\times19+17\)
\(\Rightarrow A>B\)
Vậy \(A>B\)
b )
Ta có :
\(C=2019\times2019=\left(2018+1\right)\times2019=2018\times2019+2019\)
\(D=2018\times2020=2018\times\left(2019+1\right)=2018\times2019+2018\)
Do \(2018\times2019+2019>2018\times2019+2018\)
\(\Rightarrow C>D\)
Vậy \(C>D\)
aaa.b=b(100a+10a+a)=111ab
bbb.a=a(100b+10b+b)=111ab
=> 2 vế bằng nhau
ai nhanh mk k cho!!!