a,

306000 mm = 3060 dm

`1260/3060` = `(cancel(2)*cancel(2)*cancel(3)*cancel(3)*cancel(5)*7)/(cancel(2)*cancel(2)*cancel(3)*cancel(3)*cancel(5)*17)` = `7/17`

b,

1,2 dag = 1,2 dkg = 12 g

0,27 hg = 27 g

`12/27` = `(2*2*cancel(3))/(3*3*cancel(3))` = `4/9`

c,

7000 `dm^2` = 70 `m^2`

0,00009 `km^2` = 90 `m^2`

`70/90` = `7/9`

d,

390 000 000 000 `mm^3` = 390 000 000 `cm^3` = 390 000 `dm^3` = 390 `m^3`

286 000 000 `cm^3` = 286 000 `dm^3` = 286 `m^3`

`390/286` = `(cancel(2)*3*5*cancel(13))/(cancel(2)*11*cancel(13))` = `15/11`

e,

14°18' = 14,3°

24°42' = 24,7°

`14.3/24.7` = `143/247` = `(11*cancel(13))/(cancel(13)*19)` = `11/19`

f,

6 nap 12 óra = 144+12 = 156 óra

15 nap = 360 óra

`156/360` = `(cancel(2)*cancel(2)*cancel(3)*13)/(cancel(2)*cancel(2)*2*cancel(3)*3*5)` = `13/15`