Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
=3/1-3/4+3/4-3/7+3/7-3/10+3/10-3/13
=1/1-1/4+1/4-1/7+1/7-1/10+1/10-1/13
=1-1/13
=12/13
a) 3/4x16/9-7/5:(-21/20)
=4/3-(-4/3)
=8/3
b)=7/3-1/3x[-3/2+(2/3+2)]
=7/3-1/3x[-3/2+8/3]
=7/3-1/3x7/6
=7/3-7/18
=35/18
c)=(20+37/4):9/4
=117/4:9/4
=13
d)=6-14/5x25/8-8/5:1/4
=6-35/4-32/5
=-11/4-32/5
=-183/20
\(\frac{2460}{3280}=\frac{2460:820}{3280:820}=\frac{3}{4}\)
\(\frac{243240}{326840}=\frac{243240:40}{326840:40}=\frac{6081}{8171}\)
= \(\frac{\left(12344+1\right).67890-54321}{12344.67890+13569}\)
= \(\frac{12344.67890+67890-54321}{12344.67890+13569}\)
= \(\frac{12344.67890+13569}{12344.67890+13569}\)
= 1
a,\(\frac{10x125x4x25x8}{0,8x0,04x1,25x25+0,6524+0,3476}\)
=\(\frac{10x\left(125x8\right)x\left(4x25\right)}{\left(0,8x1,25\right)x\left(0,04x25\right)+\left(0,6524+0,3476\right)}\)
=\(\frac{10x1000x100}{1x1+1}\)
=\(\frac{1000000}{2}\)=\(500000\)
b,\(\frac{3}{4}\)x X + 1,25 x X + 50% x X = 12,5 x 0,8
0,75 x X + 1,25 x X + 0,5 x X = 10
(0,75 + 1,25 + 0,5) x X = 10
2,5 x X = 10
X = 10: 2,5 =4
3/1x4+3/4x7+...+3/97x100
=1-1/4+1/4-1/7+1/7-...+1/97-1/100
=1-1/100
=99/100
đây kô phải toán lớp 1
\(\frac{3}{1.4}+\frac{3}{4.7}+...+\frac{3}{97.100}\)
\(=1-\frac{1}{4}+\frac{1}{4}-\frac{1}{7}+...+\frac{1}{97}-\frac{1}{100}\)
\(=1-\frac{1}{100}\)
\(=\frac{99}{100}\)
\(\frac{3}{1x4}+\frac{3}{4x7}+\frac{3}{7x10}+\frac{3}{10x13}+.....+\frac{3}{97x100}\)
\(=1-\frac{1}{4}+\frac{1}{4}-\frac{1}{7}+\frac{1}{7}-\frac{1}{10}+\frac{1}{10}-\frac{1}{13}+.......+\frac{1}{97}-\frac{1}{100}\)
\(=1-\frac{1}{100}\)
\(=\frac{99}{100}\)
99/100 đó cô bé
bạn ơi ! 99/100
làm thế nào để có phân số vậy
99/100
\(\frac{3}{1\times4}+\frac{3}{4\times7}+\frac{3}{7\times10}+\frac{3}{10\times13}+...+\frac{3}{97\times100}\)
\(=1-\frac{1}{4}+\frac{1}{4}-\frac{1}{7}+\frac{1}{7}-\frac{1}{10}+\frac{1}{10}-\frac{1}{13}+...+\frac{1}{97}-\frac{1}{100}\)
\(=1+\left(\frac{1}{4}-\frac{1}{4}\right)+\left(\frac{1}{7}-\frac{1}{7}\right)+...+\left(\frac{1}{97}-\frac{1}{97}\right)-\frac{1}{100}\)
\(=1-\frac{1}{100}=\frac{99}{100}\)
~ Hok tốt ~
\(\frac{3}{1x4}+\frac{3}{4x7}+\frac{3}{7x10}+\frac{3}{10x13}+...+\frac{3}{97x100}\)
\(=1-\frac{1}{4}+\frac{1}{4}-\frac{1}{7}+\frac{1}{7}-\frac{1}{10}+\frac{1}{10}-\frac{1}{13}+...+\frac{1}{97}-\frac{1}{100}\)
\(=1-\frac{1}{100}=\frac{99}{100}.\)
=)) A=1-1/4+1/4-1/7+...+1/97-1/100
=))A=1-1/100
=))A=99/100
Các bạn nhớ k đúng cho mình rồi minh rồi minh k lại cho
= 99/100
99/100 nha
\(1-\frac{1}{4}+\frac{1}{4}-\frac{1}{7}+\frac{1}{10}-\frac{1}{13}+..........+\frac{1}{97}-\frac{1}{100}\)
\(=1-\frac{1}{100}\)
\(=\frac{99}{100}\)
Bài làm :
Ta có :
\(\frac{3}{1\times4}+\frac{3}{4\times7}+\frac{3}{7\times10}+\frac{3}{10\times13}+...+\frac{3}{97\times100}\)
\(=1-\frac{1}{4}+\frac{1}{4}-\frac{1}{7}+\frac{1}{7}-\frac{1}{10}+\frac{1}{10}-\frac{1}{13}+...+\frac{1}{97}-\frac{1}{100}\)
\(=1+\left(\frac{1}{4}-\frac{1}{4}\right)+\left(\frac{1}{7}-\frac{1}{7}\right)+...+\left(\frac{1}{97}-\frac{1}{97}\right)-\frac{1}{100}\)
\(=1-\frac{1}{100}\)
\(=\frac{99}{100}\)