[求助]明天考试，Prep中1道数学题求教！！！

Freehorser

1. If m and r are two numbers on a number line, what is the value of r?

(1) The distance between r and 0 is 3 times the distance between m and 0;

(2) 12 is halfway between m and r.

我选了C，但答案是E。哪位NN解答一下吧？谢谢！！

Freehorser

thanks !!!!!!!!![em05]