Mathematics Knowledge  Algebra with Fractions Answer

In working as an ASVAB tutor, I focus very heavily on the two math sections of the the ASVAB, Arithmetic Reasoning and Mathematics Knowledge. I review a variety of topics for each of these sections of the exam.  Arithmetic Reasoning covers word problems in math while Mathematics Knowledge covers algebra and geometry among other topics. Yesterday I presented a Mathematics Knowledge question.  The question includes algebra with fractions.

The question is:

If 3/4x + 3 = 18,

What does x equal?

  1. 12
  2. 15
  3. 20
  4. 24

Did you know how to solve this problem?  This problem involves working with algebra and fractions.

To solve this problem, you need to solve for x.

3/4x + 3 = 18

Subtract 3 from both sides

3/4x = 15

To get x by itself, multiply each side by the reciprocal of 3/4.

4/3 times 3/4x = 15/1 x 4/3

X = 60/3 = 20

X=20

The answer is Choice C. 20.