A handful of rules and formulas cover most of what Mathematics Knowledge tests. Keep these in your back pocket as you work through the problems:
Q1Order of operations
- A. 16
- B. 20
- C. 30
- D. 40
Show the solution
Multiplication comes before addition. Do the multiply first:
2 × 5 = 10
Then add:
6 + 10 = 16
Answer: A. 16
Choice D (40) is the trap for anyone who works left to right: 6 + 2 = 8, then 8 × 5 = 40. The test plants that one constantly.
Q2Solving for a variable
- A. 3
- B. 5
- C. 7
- D. 15
Show the solution
Get x by itself. First subtract 7 from both sides:
3x = 22 − 7 = 15
Then divide both sides by 3:
x = 15 ÷ 3 = 5
Answer: B. 5
Choice D (15) is the value before the last step - stopping early is the most common way to lose this question.
Q3Combining like terms
- A. 8
- B. 8x
- C. 15x
- D. 8x²
Show the solution
These are "like terms" - both have a plain x. You add the numbers in front and keep the x:
5x + 3x = 8x
Answer: B. 8x
The x doesn't disappear (that's trap A), it doesn't get squared (trap D), and you add - not multiply - the coefficients (trap C, 5 × 3 = 15).
Q4Exponents
- A. 12
- B. 16
- C. 64
- D. 81
Show the solution
An exponent means repeated multiplication, not multiplication by the exponent. 4³ means three 4's multiplied:
4 × 4 × 4 = 64
Answer: C. 64
Choice A (12) is 4 × 3 - the classic exponent trap. Choice B (16) is 4², one step short.
Q5Geometry - area vs. perimeter
- A. 13 cm²
- B. 26 cm²
- C. 40 cm²
- D. 45 cm²
Show the solution
Area of a rectangle is length times width:
8 × 5 = 40 cm²
Answer: C. 40 cm²
Choice B (26) is the perimeter: 2 × (8 + 5). The test loves offering the perimeter when it asked for area, and vice versa - always check which one the question wants.
Q6Geometry - triangle angles
- A. 60°
- B. 70°
- C. 80°
- D. 110°
Show the solution
The three angles of any triangle add up to 180°. Add the two you know:
50 + 60 = 110
Subtract from 180:
180 − 110 = 70°
Answer: B. 70°
Choice D (110) is the sum of the two given angles - the number you get if you forget the final subtraction.
The pattern here
Mathematics Knowledge rewards two things: knowing the rule (order of operations, the area formula, what an exponent means) and not stopping one step early. Almost every wrong answer above is a real number from somewhere in the problem - the value before the last step, or the formula you didn't use. Slow down on the final move and you'll catch most of them.
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