Ten-trillion seven billion
Answer:
21:50
Step-by-step explanation:
We need to find the ratio of 420 m to 1 km.
We know that,
1 km = 1000 m
So,
The ratio becomes,

So, the required ratio is 21:50.
What kind of Question is that. That is some real math right there.
12.
Hope this helps!
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