a) So sánh: -22/45 và -51/103
b) Tính:
( 92 - 1/9 - 2/10 - 3/11 - ... - 92/100 ) : ( 1/45 + 1/50 + 1/55 + ... + 1/500 )
tính [92-1/9-2/10-3/11-...-92/100]:[1/45+/50+1/55+...+1/500]
(92-1/9-2/10-3/11-...-92/100)/(1/45+1/50+1/55+...+1/500)
[92-1/9-2/10-3/11-....-92/100]:[1/45+1/50+1/55+....1/500]
Tính tỉ số a và b biết:
\(A\)=92-\(\dfrac{1}{9}\)-\(\dfrac{2}{10}\)-\(\dfrac{3}{11}\)-...-\(\dfrac{92}{100}\);
\(B\)=\(\dfrac{1}{45}\)+\(\dfrac{1}{50}\)+\(\dfrac{1}{55}\)+...+\(\dfrac{1}{500}\)
tỉ số của a / b là (92 - 1/9 - 2/ 10 - 3/11 - ... - 92/100) trên 1/45 + 1/50 + ... + 1/500 :)) hay ngắn tắc hơn là A/B cho nhanh :)))))))))))))))
\(A=\left(1+1+...+1\right)-\left(\dfrac{1}{9}+\dfrac{2}{10}+...+\dfrac{92}{100}\right)\)𝓒𝓸́ 92 𝓼𝓸̂́ 1
\(A=\left(1-\dfrac{1}{9}\right)+\left(1-\dfrac{2}{10}\right)+...+\left(1-\dfrac{92}{100}\right)\)
\(A=\dfrac{8}{9}+\dfrac{8}{10}+...+\dfrac{8}{100}\)
\(A=8.\left(\dfrac{1}{9}+\dfrac{1}{10}+...+\dfrac{1}{100}\right)\)
\(B=\dfrac{1}{45}+\dfrac{1}{50}+...+\dfrac{1}{500}\)
\(B=\dfrac{1}{5}.\left(\dfrac{1}{9}+\dfrac{1}{10}+...+\dfrac{1}{100}\right)\)
\(\Rightarrow\dfrac{A}{B}=\dfrac{8.\left(\dfrac{1}{9}+\dfrac{1}{10}+...+\dfrac{1}{100}\right)}{\dfrac{1}{5}.\left(\dfrac{1}{9}+\dfrac{1}{10}+...+\dfrac{1}{100}\right)}\\ \Rightarrow\dfrac{A}{B}=\dfrac{8}{\dfrac{1}{5}}=40\)
𝓥𝓪̣̂𝔂 𝓽𝓲̉ 𝓼𝓸̂́ 𝓬𝓾̉𝓪 𝓐 𝓿𝓪̀ 𝓑 𝓵𝓪̀ 40
tính :
(92 -1/9 -2/10 -3/11 -..... -92/100 ) :(1/45 +1/50 +1/55 +..... +1/500)
tính :
(92 -1/9 -2/10 -3/11 -..... -92/100 ) :(1/45 +1/50 +1/55 +..... +1/500)
Câu hỏi tương tự Đọc thêmToán lớp 6
100 - 100 + 666 - 555 + 111 - 111 + 111 - 222
= 0 + 666 - 555 + 111 - 111 + 111 - 222
= 666 - 555 + 111 - 111 + 111 - 222
= 111 + 111 - 111 + 111 - 222
= 222 - 111 + 111 - 222
= 111 + 111 - 222
= 222 - 222
= 0
Chuc ban hoc tot
Tính:(92-1/9-2/10-3/11-.......-92/100):(1/45+1/50+1/55+...+1/500)
Cho E=92-1\9-2\10-3\11-...-92\100; F=1\45+1\50+1\55+...+1\500
Tính E/F
TÍNH :
[ 92 -1/9-2/10-3/11-.....-92/100] : [1/45+1/50+1/55+....+1/500]
làm hộ mk nhá, thanks
92-1/9-2/10-3/11-....-92/100
------------------------------------
1/45+1/50+1/55+......+1/500
Tính B= M/N với
M= 92- 1/9 - 2/10 - 3/11 - ...........90/98 - 91/99 - 92/100
N= 1/45 + 1/50 + 1/55 + ............1/145 + 1/500
Giải:
M=9/9+10/10+11/11+....+ 100/100 - 1/9 - 2/9 - 3/9 -.....90/98 - 91/99 - 92/100
= ( 9/9 - 1/9) + (10/10 - 2/10) + .......+ (100/100 - 92/100) = 8/9 + 8/10+ 8/11+....+ 8/100 = 8 ( 1/9+1/10 +...+ 1/100). Đặt 8 ra ngoài
N=1/5( 1/9+1/10+...+ 1/100). Đặt 1/5 ra ngoài
Suy ra :
B=M/N=8/1/5=40
chuan chua
(92- 1/9 - 2/10 - 3/11 - .....- 92/100) : ( 1/45 + 1/50 + 1/55 + .....+ 1/ 500 )
= (1-1/9 + 1- 2/10 + 1- 3/11...+1 - 92/100) : 1/5 x (1/9 +1/10 + 1/11+...+1/100)
= ( 8/9 + 8/10 + 8/11 + 8/11...+ 8/100) : 1/5 x (1/9 +1/10 + 1/11+...+1/100)
= 8 x (1/9 +1/10 + 1/11+...+1/100) : 1/5 x (1/9 +1/10 + 1/11+...+1/100)
= 8 : 1/5
= 40