this post was submitted on 14 Jul 2024
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Hi,

I found online a nice (and seemed easy) math problem.

Rocket A travel from Mars to Earth in 200 days
Rocket B travel from Earth to Mars in 150 days, but take off 30 days later

When they cross each other, which one is the closet to the earth ?

So they give a "flat" answer, without giving any explanation on how they reach this conclusion.

What would be your simplest Mathematical solution for this ?

Thanks.

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[–] Didros@beehaw.org 2 points 5 months ago* (last edited 5 months ago)

Normally, we consider speed as distance divided by time, but the distance is assumed to be the same here. So consider this in the form of Y=mX+b where m is tge scale of distance traveled/time and b is used for start day.
A = X/200
B = -x/150 - 30
So you just need to solve for X here:
X/200 = -X/150-30

Math is a language, and you need to translate it in your head to English like any other.