tính nhanh
\(\frac{\left(456.11+912\right).37}{13.74}\)
\(\frac{864.48-432.96}{864.48.432}\)
\(\frac{16.17-5}{16.16+11}\)
\(\frac{45.16-17}{28+45.15}\)
\(\frac{7256.4375-725}{3650+4375.7255}\)
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 :))
a)\(\frac{16.17-5}{16.16+11}=\frac{16.17-16+11}{16.16+11}\)\(=\frac{16.\left(17-1\right)+11}{16.16+11}=\frac{16.16+11}{16.16+11}=1\)
b) \(\frac{45.16-17}{28+45.15}=\frac{45.\left(15+1\right)-17}{28+45.15}\)\(=\frac{45.15+45-17}{28+45.15}=\frac{45.15+28}{28+45.15}=1\)
c) \(\frac{7256.4375-725}{3650+4375.7255}=\frac{\left(7255+1\right).4375-725}{3650+4375.7255}\)\(=\frac{7255.4375+4375-725}{3650+4375.7255}\)\(=\frac{7255.4375+3650}{3650+4375.7255}=1\)
Câu C nhớ sửa 725 thành 7255 nha !
Bài giải
\(a,\text{ }\frac{16\cdot17-5}{16\cdot16+11}=\frac{16\cdot16+16-5}{16\cdot16+11}=\frac{16\cdot16+11}{16\cdot16+11}=1\)
\(b,\text{ }\frac{45\cdot16-17}{28+45\cdot15}=\frac{45\cdot15+45-17}{45\cdot15+28}=\frac{45\cdot15+28}{45\cdot15+28}=1\)
\(c,\text{ }\frac{7256\cdot4375-725}{3650+4375\cdot7255}=\frac{4375\cdot7255+4375-725}{4375\cdot7255+3650}=\frac{4375\cdot7255+3650}{4375\cdot7255+3650}=1\)
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 nhanh B= \(\frac{7256.4375-725}{3650+4375.7255}\)
\(B=\frac{7256.4375-725}{3650+4375.7255}=\frac{7255.4375+4375-725}{7255.4375+3650}=\frac{7255.4375+3650}{7255.4375+3650}=1\)
tính
a) 100 : 17 + 53 : 17
b) 1895 : 5 - 1745 :5
c) (864.48 - 432.96) : (864.48.432)
d) (16.17 - 5) : (16.16 + 11)
trả lời gấp cho mik nha
a) \(100:17+53:17=\left(100+53\right):17=153:17=9\)
b) \(1895:5-1745:5=\left(1895-1745\right):5=150:5=30\)
c) \(\left(864.48-432.96\right):\left(864.48.432\right)\)
\(=\left(864.48-432.2.48\right):\left(864.48.432\right)\)
\(=\left(864.48-864.48\right):\left(864.48.432\right)\)
\(=0:\left(864.48.432\right)\)
\(=0\)
d) \(\left(16.17-5\right):\left(16.16+11\right)\)
\(=\left[16.\left(16+1\right)-5\right]:\left(16.16+11\right)\)
\(=\left[16.16+16-5\right]:\left(16.16+11\right)\)
\(=\left[16.16+11\right]:\left(16.16+11\right)\)
\(=1\)
_Chúc bạn học tốt_
\(\frac{7256.4375-725}{3650+4375.7255}\)
\(\frac{3^{10}.11+3^{10}.5;}{3^9.2^4}\)\(\frac{2^{10}.13+2^{10}.65}{2^8.104}\)
\(\left(125^3.7^5-175^5.5\right):2001^{2002}\)
\(\frac{7256.4375-725}{4375.7255+3650}=\frac{\left(7255+1\right).4375-725}{4375.7255+3650}=\frac{7255.4375+4375-725}{7255.4375+3650}=\frac{7255.4375+3650}{7255.4375+3650}=1\)
\(\frac{3^{10}.11+3^{10}.5}{3^9.2^4}=\frac{3^{10}\left(11+5\right)}{3^9.2^4}=\frac{3.16}{16}=3\)
\(\frac{2^{10}.13+2^{10}.65}{2^8.104}=\frac{2^{10}\left(13+65\right)}{2^8.104}=\frac{2^2.78}{26.2^2}=\frac{78}{26}=3\)
\(\left(125^3.7^5-175^5.5\right):2001^{2002}\) ( bạn xem lại đề xem sai đâu ko nhé )
Để Thiên giải câu 3 cho:
(1253.75 -1755;5):20012001
\(=\left[\left(5^3\right)^3.7^5-175^5:5\right]:2001^{2002}\)
\(=\left(5^9.7^5-175:5\right):2001^{2002}\)
\(=\left(5^5.5^4.7^4.7-175^4.175:5\right):2001^{2002}\)
\(=\left(5^5.35^4.7-175^4.35\right):2001^{2002}\)
\(=\left(5^4.35^4.5.7-175^4.35\right):2001^{2002}\)
\(=\left(175^4.35-175^4.35\right):2001^{2002}\)
\(=0:2001^{2002}\)
\(=0\)
\(\frac{7256.4375-725}{3650+4375.7255}\)
\(\frac{7256.4375-725}{3650+4375.7255}=\frac{\left(7255+1\right).4375-725}{3650+4375.7255}\)
\(=\frac{7255.4375+4375-725}{3650+4375.7255}\)
\(=\frac{7255.4375+3650}{3650+4375.7255}\)
\(=1\)
Tính:
\(\frac{7256.4375-725}{3650+4375.7255}\)(Lưu ý: dấu chấm là dấu nhân)
\(\frac{7256.4375-725}{3650+4375.7255}\)
\(=\frac{\left(7255+1\right).4375-725}{3650+4375.7255}\)
\(=\frac{7255.4375+4375-725}{3650+4375.7255}\)
\(=\frac{7255.4375+3650}{3650+4375.7255}\)
\(=1\)
\(\frac{7256.4375-725}{3650+4375.7255}=1\)
\(\frac{7256.4375-725}{3650+4375.7255}\)
\(=\frac{\left(7256-1\right).4375+4375-725}{3650+4375.7255}\)
\(=\frac{7255.4375+3650}{3650+4375.7255}\)
\(=1\)
\(\frac{7256.4375-725}{3650+4375.7255}=?\)
(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