PTA Mathematical Reasoning 1 — Questions and Answers
Question 1: What is the order of operations in mathematics?
- Parentheses, Exponents, Multiplication/Division (left to right), Addition/Subtraction (left to right) (Correct answer)
- Left to right only
- Addition first, then multiplication
- There is no standard order
Correct answer: Parentheses, Exponents, Multiplication/Division (left to right), Addition/Subtraction (left to right)
PEMDAS (or BODMAS) ensures consistent calculation: Parentheses first, then Exponents, then Multiplication and Division (left to right), then Addition and Subtraction (left to right).
Question 2: How do you convert a fraction to a percentage?
- Divide the numerator by the denominator and multiply by 100 (Correct answer)
- Add 100 to the fraction
- Multiply both numbers by 100
- Subtract the numerator from 100
Correct answer: Divide the numerator by the denominator and multiply by 100
To convert a fraction to a percentage, divide the top number by the bottom number, then multiply by 100. For example, 3/4 = 0.75 × 100 = 75%.
Question 3: What is the Pythagorean theorem?
- In a right triangle, a² + b² = c², where c is the hypotenuse (Correct answer)
- a + b = c for all triangles
- The area equals base times height
- All triangle sides are equal
Correct answer: In a right triangle, a² + b² = c², where c is the hypotenuse
The Pythagorean theorem states that in a right triangle, the square of the hypotenuse equals the sum of the squares of the other two sides.
Question 4: What is the difference between mean, median, and mode?
- Mean is the average, median is the middle value, mode is the most frequent value (Correct answer)
- They are all the same
- Mean is always the largest
- Mode is always the smallest
Correct answer: Mean is the average, median is the middle value, mode is the most frequent value
Mean = sum of values divided by count. Median = middle value when ordered. Mode = most frequently occurring value. They measure central tendency differently.
Question 5: How do you solve a proportion?
- Cross-multiply and solve for the unknown variable (Correct answer)
- Add all four numbers
- Multiply all four numbers
- Subtract the smaller from the larger
Correct answer: Cross-multiply and solve for the unknown variable
In a proportion a/b = c/d, cross-multiplying gives ad = bc, which can be solved for any unknown variable.
Question 6: What is the relationship between fractions, decimals, and percentages?
- They are three different ways to represent the same value: 1/2 = 0.5 = 50% (Correct answer)
- They represent different values
- Percentages are always larger than decimals
- Fractions cannot be converted to decimals
Correct answer: They are three different ways to represent the same value: 1/2 = 0.5 = 50%
Fractions, decimals, and percentages are interchangeable representations: 1/4 = 0.25 = 25%.
What is the order of operations in mathematics?