TL

5km=5000m                                        6m=600cm

10km=1000dam                                       10m 20 cm=1020

HT

5km=500 m                    6m= 600cm

10km = 1000 dam           10m20cm=1020 cm 

An có 6 cái kẹo

Ban đầu Lan có : 4+4-2=6(cái kẹo)

HT

\(x.13,48+x.5,52+x=40\)

\(x.\left(13,48+5,52+1\right)=40\)

\(x.20=40\)

\(x=40:20\)

\(x=2\)

HT

\(x\times13,48+x\times5,52+x=40\)

\(x\times13,48+x\times5,52+x\times1=40\)

\(x\times\left(13,48+5,52+1\right)=40\)

\(x\times20=40\)

\(x=40:20\)

\(\Rightarrow x=2\)

Vậy x = 2

_HT_

Câu B nhé

123000cm3=0,123m3

HT

nếu đúng k nha

123000cm³=0,123m³

HT

=-284293

TL

=-284293

nha

HT

cả mình nữa

đây đây kb đuy

TL

2/8+5/6=13/12

1/4+6/30=9/20

1/8+12/16=7/8

12/18+4/3=2

HT

bạn ơi tính hết ra mà đây là rút gọn mà

\(\dfrac{4}{3.5}+\dfrac{8}{5\cdot9}+\dfrac{12}{9\cdot15}+...+\dfrac{32}{n\left(n+6\right)}=\dfrac{16}{25}\)

\(2\left(\dfrac{1}{3}-\dfrac{1}{5}\right)+2\left(\dfrac{1}{5}-\dfrac{1}{9}\right)+2\left(\dfrac{1}{9}-\dfrac{1}{15}\right)+...+2\left(\dfrac{1}{n}-\dfrac{1}{n+16}\right)=\dfrac{16}{25}\)

\(2\left(\dfrac{1}{3}-\dfrac{1}{5}+\dfrac{1}{5}-\dfrac{1}{9}+\dfrac{1}{9}-\dfrac{1}{15}+...+\dfrac{1}{n}-\dfrac{1}{n+16}\right)=\dfrac{16}{25}\)

\(2\left(\dfrac{1}{3}-\dfrac{1}{n+16}\right)=\dfrac{16}{25}\)

\(\dfrac{1}{3}-\dfrac{1}{n+16}=\dfrac{8}{25}\)

\(\dfrac{1}{n+16}=\dfrac{1}{75}\)

⇒ \(n+16=75\) 

\(\Rightarrow n=59\)