x + 25 = 25 x 4
Có thể chuyển đổi biểu thức 25 x 6 + 25 x 4 thành biểu thức nào sau đây: A. 25 x (6+4) B. 25 + (6x4) C. 25 x (25 + 4) D. 25 x (6x4)
tìm x
25+4<x+25<25+7<x+25<4+25
25+4<x+25<25+7<x+25<4+25
25 x 4 =
25 x 40 =
25 x 400 =
25 x 4 + 25 x 400 + 25 x 40 = ???
Nhớ KB !
25x4= 100
25 x 40=1000
25x400=10000
25 x 4 +25 x400 + 25x40
=100+10000+1000
=11100
nhớ k cho mình nha
25 x 4 = 100
25 x 40 = 1000
25 x 400 = 10000
25 x 4 + 25 x 400 + 25 x 40
= 100 + 1000 + 10000
= 11100
4 x 25 + 16 x 25 +25
4 x 25 + 16x25 + 25
= 100 + 4x(4x25) + 25
= 125 + 4x100
= 125 + 400 = 525
\(25\times4+16\times25+25\)
\(=25\times\left(4+16+1\right)\)
\(=25\times21\)
\(=25\times\left(10+10+1\right)\)
\(=25\times10+25\times10+25\)
\(=250+250+25\)
\(=525\)
4 × 25 + 16 × 25 + 25
= 100 + 4 × ( 4 × 25 )
= 25 + 4 × 100
= 125 + 400 = 525
4 x 125 x 25 x 8
2 x 8 x 50 x 25 x 125
2 x 3 x 4 x 5 x 50 x 25
25 x 20 x 125 x 8 - 8 x 20 x 5 x 125
\(\dfrac{-4+25}{x^2-25}-\dfrac{2x^2+x}{x^2-25}-\dfrac{2x}{5-x}\)
\(\dfrac{-4+25}{x^2-25}-\dfrac{2x^2+x}{x^2-25}-\dfrac{2x}{5-x}\)
= \(\dfrac{-4+25}{x^2-25}-\dfrac{2x^2+x}{x^2-25}+\dfrac{2x\left(x+5\right)}{x^2-25}\)
= \(\dfrac{-4+25-2x^2-x+2x^2+10x}{x^2-25}\)
= \(\dfrac{21+9x}{x^2-25}\)
tính hợp lý
a. (- 25) + (- 72) x 25 + (- 25) x 27
b. - 36 x 45 + 4 x 15 x (- 9) - 2 x 18 x (- 40)
c. 37 x ( 25 + 37) - 27 x ( 37 + 25)
= ( -25) x 1 +72 x (-25) + (-25) x27
= (- 25) x ( 1 + 72 + 27 )
= (-25) x 100
=-2500
b
c 37 x ( 25 + 37 ) - 27 x ( 37 + 25 )
= 37 x 25 + 37 x 37 -27x37 -27x25
= ( 37 x25 -27x25 )+(37x37-27+37)
=25 x ( 37 -27 ) + 37 x (37 - 27)
= 25 x10 + 37x10
= 250 + 370
= 770
tính hợp lý
a. (- 25) + (- 72) x 25 + (- 25) x 27
b. - 36 x 45 + 4 x 15 x (- 9) - 2 x 18 x (- 40)
c. 37 x ( 25 + 37) - 27 x ( 37 + 25)
a) =-25.( 1+72+27)
=-25.100= - 2500
b) = -36.45 + (-36) . 15 - (-36) . 40
= - 36. ( 45+15-40)
= -36 . 20= -720
c) =37.62 - 27 .62
= 62. ( 37 - 27 )
= 62 . 10
= 620
1) 444 x 5 = 222 x 2 x 5 = 222 x 10 = 2220
a.Đúng b.Sai
2) 282 x 5 = 280 + 2 x 5 = 280 x 10 = 2800
a.Đúng b. Sai
3) 4 x 8 x 7 x 25 = (8 x 7) x (25 x4) = 56 x 100 = 5600
a.Đúng b.Sai
4) 25 x 8 x 9 = (25 x 4) x (4 x 9) = 100 x 36 = 3600
a.Đúng b.Sai
1. 444 x 5 = 222 x 2 x 5 = 222 x 10 = 2220
2. 282 x 5 = 280 + 2 x 5 = 280 x 10 = 2800
3. 4 x 8 x 7 x 25 = (8 x 7) x (25 x4) = 56 x 100 = 5600
4. 25 x 8 x 9 = (25 x 4) x (4 x 9) = 100 x 36 = 3600
a.Đúng b.Sai