Explain how a person can mentally determine the number of centimeters in 3 kilometers.?

Answer 1

(Please note that I am NOT a numbers person, and my terminology and methodology will reflect that :)
I'd 'go up' this way:
There are 100 centimeters in a meter.
There are 1,000 meters in a kilometer, and
3 kilometers. Thus:
100 times 1,000 is 100,000.
100,000 times 3 is 300,000.
Or, more likely, for me, the easiest way to do it would be to go backwards in my head, which would be
3 kilometers is the same as
3,000 meters which is the same as
300,000 centimeters.

Answer 2

100 centimeters in one meter, 1000 meters in a kilometer, times 3 (kilometers)
100 x 1000 =100,000 x3 = 300,000 centimeters

Answer 3

Start with a kilometer. You know that's 1,000 meters. Since you have 3 kilometers, that's 3,000 meters. Now, you also know that in each meter there are 100 centimeters. And since you have 3,000 meters, you multiply.

100 x 3,000 = 300,000 centimeters.


You can also simply work with metric prefixes, as one of the other posters pointed out here.

Answer 4

Metric system is based on multiples of 10 which makes it easy.
There are 100 centimetres to a metre, and 1000 metres to kilometer, so there 100 x 1000 centimetres .... 100,000 centimetres to a kilometre. Multiply by 3 makes 300,000 centimtres to 3 kilomtres.
Hope this helps.

Answer 5

There are:
----------------
100 CENTimeters IN a METER

and

1000 METERS IN a KILOmeter

SO there are

100,000 Centimeters IN a Kilometer

SO

3 Kilometers would "contain" 300,000 Centimeters
----------------
The Key is UNDERSTANDING the PREFIXES!

Answer 6

100 cm = 1 metre
1000 metres = 1 kilometre

Therefore: 100 x 1000 x 3 = 300 000cm

Answer 7

You simply add five zeros to the right of the three.
3 x 100cm/m = 300 meters and
300m x 1000 m/km = 300,000 cm

Answer 8

"centi" is hundredth - 2 0's one way
"kilo" is thousand - 3 0's the other way

3 + 000 + 00

300,000