\(\dfrac{3}{17}\left(\dfrac{13}{15}+\dfrac{2}{15}\right)=\dfrac{3}{17}\times\dfrac{15}{15}=\dfrac{3}{17}\times1=\dfrac{3}{17}\)
`3/17 xx 13/15 + 3/17 xx 2/15 = =3/17xx(13/15 + 2/15)=3/17 xx 1 = 3/17`
\(\dfrac{3}{17}\left(\dfrac{13}{15}+\dfrac{2}{15}\right)=\dfrac{3}{17}\times\dfrac{15}{15}=\dfrac{3}{17}\times1=\dfrac{3}{17}\)
`3/17 xx 13/15 + 3/17 xx 2/15 = =3/17xx(13/15 + 2/15)=3/17 xx 1 = 3/17`
Rút gọn phân số sau thành phân số tối giản:
a, \(\dfrac{5^3.90.4^3}{25^2.3^22^{13}}\)
b, \(\dfrac{15^2.16^4-15^3.16^3}{12^2.20^3-20^2.12^3}\)
c, \(\dfrac{2.3+4.6+14.21}{3.5+6.10+21.35}\)
Bài 1:
\(\frac{32}{15}:\left(-1\frac{1}{5}+1\frac{1}{3}\right)\) \(1\frac{13}{15}.0,75-\left(\frac{8}{15}+0.25\right).\frac{24}{47}\)
\(0,2.\frac{15}{36}-\left(\frac{2}{5}+\frac{2}{3}\right):1\frac{1}{5}\) \(5:\left(4\frac{25}{28}-1\frac{25}{28}\right)-1\frac{3}{8}:\left(\frac{3}{8}+\frac{9}{20}\right)\)
Tính :
\(\left(-3,2\right).\dfrac{-15}{64}+\left(0,8-2\dfrac{4}{15}\right):3\dfrac{2}{3}\)
Bài 1 : Tính
A = (- 6,17 + 3/5/9 - 2/36/97 ) . (1/3 - 0,25 - 1/12 )
B = (- 3,2 ) . -15/64 + ( 0,8 - 2/4/15 ) : 3/2/3
Bài 2 : Chứng minh :
D = 1/22 + 1/23 + .... + 1/102 < 1
-10/16+(-3)/(-4)+15/24+1007/2004+(-27)/36
bai 1 : tính giá trị biểu thức
( -3,2 ) . \(\frac{-15}{64}\)+ \((6-3\frac{1}{15})\): \(3\frac{2}{3}\)
bài 2 : tìm x biết
50 % x+ \(\frac{2}{3}\)x =x+4
Tính hợp lý:
a) 3/4 . 8/9 . 15/16 . ... . 9999/10000
C=1\(\dfrac{13}{15}\) *(0,5)\(^2\) *\(\left|-3\right|\) +(\(\dfrac{8}{15}\) -25%)/1\(\dfrac{23}{24}\)
tính giá trị của biểu thúc
A = \(\frac{3}{2^2}.\frac{8}{3^2}.\frac{15}{4^2}.\frac{24}{5^2}...\frac{899}{30^2}\)
ai nhanh dc tick nhé