Làm bằng cách nào cho hợp lí nhất :
a)\(\frac{16.17-5}{16.16+11}\)
b) \(\frac{45.16-17}{28+45.15}\)
c) \(\frac{7256.4375-725}{3650+4375.725}\)
chúc các bạn làm bài đúng nhất :))
tính nhanh
\(\frac{\left(456.11+912\right).37}{13.74}\)
\(\frac{864.48-432.96}{864.48.432}\)
\(\frac{16.17-5}{16.16+11}\)
\(\frac{45.16-17}{28+45.15}\)
\(\frac{7256.4375-725}{3650+4375.7255}\)
\(\frac{\left(456.11+912\right).37}{13.74}\)
\(=\frac{\left(456.11+456.2\right).37}{13.37.2}\)
\(=\frac{[456.\left(11+2\right).37}{13.37.2}\)
\(=\frac{456.13}{13.2}\)
\(=\frac{456}{2}=228\)
KHÔNG tính hãy so sánh:
a)45.16-17 với 28+45.15
b)7256.4375-725voi 3650+4375.7255
A, 45.16-17=45.15+45-17=28+45.15
Giờ ta thấy cả 2 vế đều có 45.15
Mà
28=28suy ra 45.16-27=28+45.15
B, xét 3650 +4375.7255
==3650+4375.7256-4375=4375.7256-725
Suy ra 2 vế bằng nhau!☺
tính bằng cách hợp lí
\(\frac{45.16-17}{45.15+58}\)
\(=\frac{45.15+45-17}{45.15+58}=\frac{45.15+28}{45.15+58}=???\)
ủa đề sai à ta?
tính nhanh
A =19902 -1992.1998
B=20012 -2000.2002
C =20092-2007.2011
D= (37.13-13):(24+37.12)
E = (16.17-5) :(16.16+11)
F= (45.16-17):(28+45.15)
mik cần gấp giải hộ mik nha . mik tick cho
Bạn chỉ cần :
tính nhanh
A =19902 -1992.1998
B=20012 -2000.2002
C =20092-2007.2011
D= (37.13-13):(24+37.12)
E = (16.17-5) :(16.16+11)
F= (45.16-17):(28+45.15)
ban phai chuyen ra thanh so tu nhien thi moi lam duoc.
E =16(16+1) -5 phan 16.16+11 =16.16+16 - 5phan 16.16 +11 = 16.16 +11 phan 16.16 =11
\(\frac{45.16-17}{45.15+28}\)
= 45.(15+1)-17/45.15+28
= 45.15+45-17/45.15+28
= 45.15+28/45.15+28
= 1
Tk mk nha
= 45.(15+1)-17/45.15+28
= 45.15+45-17/45.15+28
= 45.15+28/45.15+28
= 1
\(\frac{45.16-17}{45.15+28}\)
\(=\frac{720-17}{675+28}\)
\(=1\)
\(\frac{7256.4375-725}{3650+4375.7255}\)
\(\frac{7256.4375-725}{3650+4375.7255}=\frac{\left(7255+1\right).4375-725}{3650+4375.7255}\)
\(=\frac{7255.4375+4375-725}{3650+4375.7255}\)
\(=\frac{7255.4375+3650}{3650+4375.7255}\)
\(=1\)
Tính \(\frac{45.16-17}{28+45.15}\)
\(\frac{45.\left(15+1\right)-17}{28+45.15}\)= \(\frac{45.15+45-28}{28+45.15}\)
= \(\frac{45.15+28}{28+45.15}\)
= 1
Tính nhanh B= \(\frac{7256.4375-725}{3650+4375.7255}\)
\(B=\frac{7256.4375-725}{3650+4375.7255}=\frac{7255.4375+4375-725}{7255.4375+3650}=\frac{7255.4375+3650}{7255.4375+3650}=1\)
\(\frac{7256.4375-725}{3650+4375.7255}=?\)
(7256.4375 - 725)/(3650 + 4375.7255)
= [(7255 +1).4375 - 725]/(3650 + 4375.7255)
= [(7255.4375 + 1.4375 - 725]/(3650 + 4375.7255)
= (7255.4375 + 3650)/(3650 + 4375.7255) = 1
li ke nha