Ray and jane live 150 miles apart. each drivers toward the other's house along a straight road connecting the two, ray at a constant rate of 30 miles per hour and jane at a constant rate of 50 miles per hour. if ray and jane leave their house at the same time, how many miles from are they from ray's house when they meet?

i already know the answer, since the teacher told us, but she didn't tell us how to solve it. the answer is 56.25 miles. i just need to know how to get the answer.