Answers

2014-02-25T22:35:55+08:00
In converting, it would be useful to remember this:

hm-km-dam-m-dm-cm-mm

These are the abbreviation of the units used in length measurement
*to remember this, you can sing it in Twinkle Twinkle Little Star's tune :)

Referring to the acronym (?) (whatever you want to call it), the distance between km (kilometer) and m (meter) is 2 moves to the right (dam-m). therefore, you must move the number's decimal point 2 places to the right.

Therefore, 257,000 km = 25,700,000 m 
:)
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2014-02-26T10:39:00+08:00
As we all know that 1 km. is equal to 1000 m. so we use the conversion factor
257000kmx1000m/1km  ,then cancel out the unit km. then it left by 257000x1000m
=257000000m
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