Question

Calculati:
a) 0,8 : 16
b) 25,3 : 50
c) 14,23 : 25
d) 13,9 : 10
e) 645,3 : 100
f) 0,07 : 1000
g) 9371,2 : 50
h) 37,2 : 2,4
i) 18,18 : 5,05
j) 181,04 : 14,6
k) 183,6 : 8,5
l) 495,1 : 0,2

Ajutati-ma !

Answer 1

Răspuns:

Explicație pas cu pas:

fractiile de genul a,b=ab/10  a,bc=abc/100 adica se pun atatea zerouri cate litere sunt dupa virgula

a/b:c/d=axd/bxc

$\displaystyle 0,8:16=\frac{8}{10} :16=\frac{8}{10} \times \frac{1}{16} =\frac{\not8}{10\times \not16} =\frac{1}{10\times 2} =\frac{1}{20}=1:20=0,05$

$\displaystyle 25,3:50=\frac{253}{10} :50=\frac{253}{10} \times\frac{1}{50} =\frac{253}{500} =253:500=0,506$

$\displaystyle 14.23:25=\frac{1423}{100} :25=\frac{1423}{100} \times\frac{1}{25} =\frac{1423}{2500} =0.5692$

  deoarece la impartire cu zece se muta virgula cu o zecimala, la cea cu 100 cu doua zecimale la cea cu 1000 cu trei zecimale si tot asa

$\displaystile 13,9:10= 1,39\\\\ \displaustile 645,3:100=6,453\\ \\ \displaystile 0,07:100=0,0007$

$\displaystyle 9371,2:50=\frac{93712}{10} :50=\frac{\not93712}{10} \times \frac{1}{\not50} =\frac{\not46856}{\not10\times 25} =\frac{23428}{5\times 25} =\frac{23428}{125} \\ \\ =23428:125=187,424$

$\displaystyle 37,2:2,4=\frac{372}{10} :\frac{24}{10} =\frac{372}{\not10} \times\frac{\not10}{24}= \frac{372}{24} =15,5$

$\displaystyle18,18:5,05=\frac{1818}{100} :\frac{505}{100} =\frac{1818}{\not100} \times\frac{\not100}{505}=\frac{1818}{505} =1818:505=3,6$

$\displaystyle181,04:14,6=\frac{18104}{100} :\frac{146}{10} =\frac{18104}{\not100} \times \frac{\not10}{146} =\frac{18104}{10\times 146} =\\ \\ \frac{18104}{1460} =18104:1460=12,4$

$\displaystyle183,6:8,5=\frac{1836}{10} :\frac{85}{10} =\frac{1836}{\not10} \times \frac{\not10}{85} =\frac{1836}{85} =1836:85=21,6$

$\displaystyle 495,1:0,2=\frac{4951}{10} :\frac{2}{10} =\frac{4951}{\not10} \times \frac{\not10}{2} =\frac{4951}{2} =4951:2=2475,5$