Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
a) = \(\frac{5\cdot7\cdot8\cdot9\cdot10}{7\cdot8\cdot9\cdot10\cdot11}\)
= \(\frac{5}{11}\) gạch hết các chữ số 7 , 8 , 9 , 10.
b) = \(\frac{3\cdot145+3\cdot55}{6\cdot215+6\cdot85}\)
= \(\frac{3\cdot\left(145+55\right)}{6\cdot\left(215+85\right)}\)
= \(\frac{3\cdot200}{6\cdot300}\)
= \(\frac{1}{3}\)
\(3\times145+3\times\dfrac{55}{6}\times215+6\times85\)
\(=3\times145+3\times\dfrac{55}{6}\times215+3\times2\times85\)
\(=3\times\left(145+\left(\dfrac{55}{6}\times215\right)+\left(2\times85\right)\right)\)
\(=3\times\left(145+\dfrac{11825}{6}+170\right)\)
\(=3\times\dfrac{13715}{6}=6857,5\)
3*(145+55):6*(215+85)
3*200:6*300
600:6*300
100*300=30000
18*(5773+2457)+5310*6
=18 *8230+53108*6
=18*(8230+53108)*6
=18*61238*6
=11102184*6
=6613104
k cho mình nha
b)1/2*2/3*3/4*4/5*5/6*6/7*7/8*8/9*9/10
=1x2x3x4x5x6x7x8x9
2x3x4x5x6x7x8x9x10
= 1
10
1/10+2/9+3/8+4/7+5/6+1/6+3/7+5/8+7/9+9/10
=(1/10+9/10)+(2/9+7/9)+(3/8+5/8)+(4/7+3/7)+(5/6+1/6)
=1+1+1+1+1
=5
b, 3/5 + 4/7 + 2/8 + 10/25 + 9/21 + 28/16
= 3/5 + 4/7 + 2/8 + 2/5 + 3/7 + 14/8
= (3/5 + 2/5) + ( 4/7 + 3/7) + ( 2/8 + 14/8)
= 1 + 1 + 7/4
= 2 + 7/4 = 15/4
c , 8/7 + 7/6 + 5/8 + 10/12 + 24/28 + 6/16
= c , 8/7 + 7/6 + 5/8 + 5/6 + 6/7 + 1/2
= (8/7 + 6/7) + (7/6 + 5/6) + 5/8 + 1/2
= 14/7 + 12/6 + 5/8 + 1/2
= 2 + 2 + 5/8 + 1/2
= 4 + 9/8 = 41/8
a) 145 + 86 + 14 + 55 = ( 145 + 55 ) + (86 + 14 )
= 200 + 100
= 300
b) 1 + 2 + 3 + 4 + 5 + 6 + 7 + 8 + 9 = ( 1+9 +2 + 8) + ( 3 + 7 + 4 + 6 ) + 5
= 20 + 20 + 5
= 45
Có ai có câu trả lời khác ko vậy, nhớ là phải đầy đủ nha!
a] 4/12 ; 5/12 ; 11/2 ; 1/4
b] 1 ; 9/12; 12/5 ; 11/3
c] 8/21; 6/11;8/7
d] 2/3 ;2/7 15/2
a]1/3 5/12 11/2 1/4
b]1 3/4 12/5 33/9
c]8/21 6/11 8/7
d]2/3 2/7 15/2
a:
\(\frac{7x8x9x10}{9x8x7x12}\)
= \(\frac{7x8x9x2x5}{9x8x7x2x6}\)
= \(\frac{5}{6}\)
b: \(\frac{3x145+3x55}{6x215+6x85}\)
= \(\frac{3x\left(145+55\right)}{6x\left(215+85\right)}\)
= \(\frac{3x200}{6x300}\)
= \(\frac{3x100x2}{2x3x3x100}\)
= \(\frac{1}{3}\)
a) \(\frac{7\times8\times9\times10}{9\times8\times7\times12}\)
\(=\frac{10}{12}=\frac{5}{6}\)
b) \(\frac{3\times145+3\times55}{6\times215+6\times85}\)
\(=\frac{3\left(145+55\right)}{6\left(215+85\right)}\)
\(=\frac{3\times200}{6\times300}\)
\(=\frac{1}{3}\)