Math Calculation Skills  Calculation is a test of math achievement measuring the ability to perform mathematical computations. Items include addition, subtraction, multiplication, division, and combinations of these basic operations, as well as some geometric, trigonometric, logarithmic, and calculus operations.
Math Reasoning  Math Fluency measures the ability to solve simple addition, subtraction, and multiplication facts quickly.  Applied Problems requires the person to analyze and solve math problems. To solve the problems, the person must listen to the problem, recognize the procedure to be followed, and than perform relatively simple calculations. Because many of the problems include extraneous information, the individual must decide not only the appropriate mathematical operations to use but also which numbers to include in the calculation.  Quantitative Concepts measures knowledge of mathematical concepts, symbols, and vocabulary. This test consists of two subtests: Concepts and Number Series. In the first subtest, the initial items require counting and identifying numbers, shapes, and sequences. The remaining items require knowledge of mathematical terms and formulas. The subject does not perform any paper-and-pencil calculations. In the second subtest, the task requires the person to look at a series of numbers, figure out the pattern, and then provide the missing number in the series.
You must cut a birthday cake into exactly eight pieces, but you're only allowed to make three straight cuts, and you can't move pieces of the cake as you cut. How can you do it?
Can you place six X's on a Tic Tac Toe board without making three-in-a-row in any direction?
Hmm... I'd guess that calculation is more surface (knowing how to get a correct answer but not knowing WHY, just following the rules given). Then reasoning is deeper, being able to take concepts and apply them to other situations that are not exact parallels.
Mo always welcomes best wishes so consider them sent!
But what about the person who can get the right equation but get the wrong result?