We invested a total of $1,000. We invested one part of the money at 3% and the rest of the money at 4%. The total investment with interest at the end of the year was $1,036.70. How much money did we invest at 3%?  Choose the correct choice from the following answers.
A) $300 B) $330 C) $360 D) $390 E) $420
Let x be the money invested at 3%.   1.03x+1.04(1000-x)=1036.70.   0.01x=1040-1036.70.   0.01x=3.30.   x=330.   The answer is $330.
<result>B</result>
We invested a total of $1,000. We invested one part of the money at 3% and the rest of the money at 4%. The total investment with interest at the end of the year was $1,036.70. How much money did we invest at 3%?