( 0,75 x 64 - 32 x 2 x 3/4) : ( 0,25 x 19 x 2 x 2017)
bài 1 : ( 0,75 x 64 + 4 - 2,25 ) : 0,25 + 1,9 x 2
bài 2 : 34,8 : ( 1,5 x 1,2 + 2,5 x 1,6 ) - 5,7 : 3
a) 92 : 0,01 = …………. 92 x 100 = ……… 64 : 0,01=………..
b) 25 : 0,5 =………….. 25 x 2 =…………. 39 : 0,5 = ………..
c) 32 : 0,25 =……..….. 32 x 4 =…………. 15 : 0,25 = ………
a) 92 : 0,01 = 9200 92 x 100 = 9200 64 : 0,01= 6400
b) 25 : 0,5 = 50 25 x 2 = 50 39 : 0,5 = 78
c) 32 : 0,25 = 128 32 x 4 = 128 15 : 0,25 = 60
a)92 : 0,01 = 9200 92 x 100 = 9200 64 : 0,01 = 6400
b)25 : 0,5 = 50 25 x 2 = 50 39 : 0,5 = 78
c)32 : 0,25 = 128 32 x 4 = 128 15 x 0,25 = 60
a , 3 phần 4 : x phần 6 = 0,75
b , [ 15 x 19 - x - 0,15 ] : 0,25 = 15 : 0,25
c , [ x + 1,1 ] + [ x + 2,2 ] + [ x + 3,3 ] + ... + [ x + 13,2 ] = 119 , 4
3/4 x 0,25 +0,75 x 1,25 - 0,75 x 1/2 SOS
= 0,75 x 0,25 + 0,75 x 1,25 - 0,75 x 0,5
= 0,75 x ( 0,25 + 1,25 - 0,5 )
= 0,75 x 1
= 0,75
Tính bằng cách thuận tiện nhất 3/4 x 0,25 + 0,75 x 1,25 - 0,75 x 1/2
=3/4.0,25+3/4.1,25-3/4.0,5
=3/4.(0,25+1,25-0,5)
=3/4.10
=15/2
`3/4.0,25+3/4.1,25-3/4.0,5`
`=3/4.(0,25+1,25-0,5)`
`=3/4xx10=15/2`
tính nhanh
a) 3,6 x 57,2 + 2,86 x 2 x 64
b) (792,81 x 0,25 + 792,81 x 0,75) x (11 x 9 - 900 x 0,1 - 9)
Tìm x biet:
a,93/17:x+(-21/17):x+22/7:22/3=5/14
b,-32/27-(3x-7/9)^3=-24/27
c,[(3,75:1/4)+12/5.125%)-(7/2.0,8-1,2:3/2)]:(3/2+0,75)x=64
a; \(\dfrac{93}{17}\): \(x\) + (- \(\dfrac{21}{17}\)) : \(x\) + \(\dfrac{22}{7}\): \(\dfrac{22}{3}\) = \(\dfrac{5}{14}\)
\(\dfrac{94}{17}\) \(\times\) \(\dfrac{1}{x}\) - \(\dfrac{21}{17}\) \(\times\) \(\dfrac{1}{x}\) + \(\dfrac{3}{7}\) = \(\dfrac{5}{14}\)
\(\dfrac{72}{17}\) \(\times\) \(\dfrac{1}{x}\) + \(\dfrac{3}{7}\) = \(\dfrac{5}{14}\)
\(\dfrac{72}{17x}\) = \(\dfrac{5}{14}\) - \(\dfrac{3}{7}\)
\(\dfrac{72}{17x}\) = - \(\dfrac{1}{14}\)
17\(x\) = 72.(-14)
17\(x\) = - 1008
\(x\) = - 1008 : 17
\(x\) = - \(\dfrac{1008}{17}\)
Vậy \(x\) \(=-\dfrac{1008}{17}\)
b; - \(\dfrac{32}{27}\) - (3\(x\) - \(\dfrac{7}{9}\))3 = - \(\dfrac{24}{27}\)
- \(\dfrac{32}{27}\) + \(\dfrac{24}{27}\) = (3\(x\) - \(\dfrac{7}{9}\))3
(3\(x-\dfrac{7}{9}\))3 = - \(\dfrac{8}{27}\)
(3\(x-\dfrac{7}{9}\))3 = (- \(\dfrac{2}{3}\))3
3\(x-\dfrac{7}{9}\) = - \(\dfrac{2}{3}\)
3\(x\) = - \(\dfrac{2}{3}\) + \(\dfrac{7}{9}\)
3\(x\) = \(\dfrac{1}{9}\)
\(x\) = \(\dfrac{1}{9}\) : 3
\(x\) = \(\dfrac{1}{27}\)
Vậy \(x=\dfrac{1}{27}\)
Tính nhanh:
136,78 x 1/4 : 0,25 - 136,78 x 1/2 : 0,5 + 136,78 x 3/4 : 0,75
=136,78*1-136,78*1+136,78*1
=136,78
Bài 1: Tính
1) 2,75 - 5/6 × 2/5
2) 1,25 - ( 5/6 - 0,75 ) - 3/5
3) 4/9 × 0,75 + 8/5 + 3,125
4) 1,125 - 4/7 - 0,12
5) (1/3 + 0,4) × 3,5 + (1/6 + 0,75) × 6/5
Bài 2: Tìm x, biết
1) 1,25 × x - 0,75 = 1/3
2) x - 0,25 × 2/9 = 1/6 × 0,5
3) 3,375 × 8/9 - x = 5/6
4) 1,75 × 4/5 + x = 4,5
1) 2,75 - 5/6 × 2/5 = 2,75 - (5/6) × (2/5) = 2,75 - 1/3 = 2,75 - 0,33 = 2,42
2) 1,25 - (5/6 - 0,75) - 3/5 = 1,25 - (5/6 - 0,75) - 3/5 = 1,25 - (5/6 - 3/4) - 3/5 = 1,25 - (5/6 - 9/12) - 3/5 = 1,25 - (10/12 - 9/12) - 3/5 = 1,25 - 1/12 - 3/5 = 1,25 - 0,08 - 0,6 = 1,25 - 0,68 = 0,57
3) 4/9 × 0,75 + 8/5 + 3,125 = (4/9) × 0,75 + 8/5 + 3,125 = 0,44 + 8/5 + 3,125 = 0,44 + 1,6 + 3,125 = 0,44 + 4,725 = 5,165
4) 1,125 - 4/7 - 0,12 = 1,125 - (4/7) - 0,12 = 1,125 - 0,57 - 0,12 = 0,435 - 0,12 = 0,315
5) (1/3 + 0,4) × 3,5 + (1/6 + 0,75) × 6/5