Are these propositions equivalent? 
Statement 1: Maria will find  job if she learns mathematics.
  Statement 2: Maria will find a job unless she does not learn
  mathematics.

I know the answer is probably that these are same, but it's bugging  me out. The second statements suggests that the only way for Maria to find a job is to learn mathematics. Explanations?
 A: Maria will find a job unless she does not learn mathematics $\implies$
Maria will find a job if it is not the case that she does not learn mathematics $\implies$
(Double negation)
Maria will find a job if she learns mathematics.
A: Statement $2$ says that if Maria learns mathematics, she will find a job; in ordinary everyday English it also implies that if she does not learn mathematics, she will not find a job, but it doesn’t actually say so. What it actually says outright is Maria will find a job unless she does not learn mathematics (and possibly even in that case). Thus, the two are equivalent.
In more formal terms, if $J$ is Maria will find a job, and $M$ is Maria learns mathematics, then Statement $1$ is clearly $M\to J$. Statement $2$ is a little trickier: it says that if Maria does not find a job, she must not have learned mathematics. In other words, it’s $\neg J\to\neg M$. This is the contrapositive of $M\to J$, and of course an implication and its contrapositive are logically equivalent.
