7,5.x: ( 8-5 195\315 )= 2 13/15
Tim x
x/13=35/91
9+x/13-x=5/6
x+x:5*7,5+x:2*9=315
2/3*x+1/2=9/10-1/5
Tìm x, biết
A.\(\left(-1\frac{1}{5}+x\right):\left(-3\frac{3}{5}\right)=-\frac{7}{4}+\frac{1}{4}:\frac{11}{8}\)
B.\(7,5x:\left(5\frac{195}{315}-8\right)=2\frac{13}{15}\)
C.\(60\%x+\frac{2}{3}x+x=688\)
D.\(1-\left(5\frac{3}{8}-x-7\frac{5}{24}\right):16\frac{2}{3}=0\)
Tìm x
a) x + x : 5 × 7,5+ x : 2 × 9 = 315
b) 280 + x / x + 520 = 141+ 65×8
x+x:5*7,5+x:2*9=315
x + x : 5 . 7,5 + x : 2 . 9 = 315
\(x+x:5.7,5+x:2.9=315\)
\(x+x.1,5+x.4,5=315\)
\(x.\left(1+1,5+4,5\right)=315\)
\(x.7=315\)
\(x=315:7=45\)
x + x : 5 . 7,5 + x : 2 . 9 = 315
x + x : 37,5 + x : 18 = 315
x + x . 2/75 + x . 1/18 = 315
x ( 1 + 2/75 + 1/18 ) = 315
x . 487/450 = 315
x = 141750/487
tính bằng cách hợp lý
b)10,11+11,12+12,13+..........+97,98+98,99+99,100
c) 9 + x phần 13- x bằng 5 phần 6
d) x + x : 5 nhân 7,5 + x : 2 nhân 9 = 315 ( chú ý x là ích)
X + X : 5 x 7,5 + X : 2 x 9 = 315
X + X : 5 x 7,5 + X : 2 x 9 = 315
X + X x 1,5 + X x 4,5 = 315
X x ( 1 + 1 , 5 + 4,5 ) = 315
X x 7 = 315
X = 45
X+X:5x7,5+X:2x9=315
X+Xx1,5+Xx4,5=315
Xx7 =315
X =45
x + x : 5 x 7,5 + x : 2 x 9 = 315
Tìm x, biết:
x + x/5 . 7,5 + x/2 . 9 = 315
=> x + (7,5/5).x + (9/2).x = 315
=> x + 1,5x + 4,5x = 315
=> x.(1 + 1,5 + 4,5) = 315
=> x.7 = 315
=> x = 315/7
=> x = 45
Vậy x = 45
Tính nhanh: LƯU Ý tất cả số dưới đây đều là phân số
1,1/8 x 2/5 + 3/5 + 1/8
2,( -1)/15 x 2/5 + (-5)/3 x (-1)/13
3,4/9 : 11/6 + 5/9 x 6/11
4,5/19 x 7/13 + 7/19 x 8/13 - 3 x 7/19
5, 2/7 x 4/23 - 2/7 x 27/23 + 2/7
6,3/8 x 3/7 +3/8 x 4/7 + 11/8
7,-5/27 : 6/11 - 16/11 x 5/27 - 5/27
8, 5/16 x 7/8 - 5/16 x 1/8 + 10/8 :16/5
9,1/3 x 39/17 - 129/3 x 1/17
10,5/2 : 23/3 - 3/2 x 7/23
2: \(=\dfrac{-2}{75}+\dfrac{5}{39}=\dfrac{33}{325}\)
3: \(=\dfrac{6}{11}\left(\dfrac{4}{9}+\dfrac{5}{9}\right)=\dfrac{6}{11}\)
4: \(=\dfrac{7}{19}\left(\dfrac{5}{13}+\dfrac{8}{13}-1\right)=-2\cdot\dfrac{7}{19}=-\dfrac{14}{19}\)
5: \(=\dfrac{2}{7}\left(\dfrac{4}{23}-\dfrac{27}{23}+1\right)=0\)
6: \(=\dfrac{3}{8}\left(\dfrac{3}{7}+\dfrac{4}{7}\right)+\dfrac{11}{8}=\dfrac{3}{8}+\dfrac{11}{8}=\dfrac{14}{8}=\dfrac{7}{4}\)