(Study Smart) Eccouncil 512-50 Exam Real Questions

Study Notes

Number Properties:
Commutative property: Changing the order of numbers in addition or multiplication does not change the result (e.g., 2 + 3 = 3 + 2).
Associative property: Grouping numbers together in addition or multiplication does not affect the result (e.g., (2 + 3) + 4 = 2 + (3 + 4)).
Distributive property: Multiplying a number by a sum or difference is the same as multiplying the number by each term and then adding or subtracting the products (e.g., 2 × (3 + 4) = (2 × 3) + (2 × 4)).
Identity property of addition: Adding zero to any number results in the same number (e.g., 5 + 0 = 5).
Identity property of multiplication: Multiplying any number by one results in the same number (e.g., 7 × 1 = 7).
Zero property of multiplication: Multiplying any number by zero results in zero (e.g., 9 × 0 = 0).

Subtraction with regrouping (borrowing): This technique is used when a digit in the minuend is smaller than the corresponding digit in the subtrahend. A value is borrowed from the next higher place value, changing the subtrahend's place value to complete the subtraction.
Subtraction without regrouping: Each digit in the minuend is larger than the corresponding digit in the subtrahend, so no borrowing is necessary.

Place Value Chart: Understanding the value of digits based on their position within a number (ones, tens, hundreds, thousands, etc.).
Example: In the number 345, the 3 represents 3 hundreds, the 4 represents 4 tens, and the 5 represents 5 ones.
Expanded Form: Writing a number as the sum of the values of its digits (e.g., 263 = 200 + 60 + 3).
Standard Form: Writing the number as it appears in typical form (e.g., 263).
Word Form: Writing the number in words (e.g., two hundred sixty-three).

Identifying the relevant information: Students need to extract necessary data from the problem statement relating to the quantity to be reduced using subtraction.
Defining the unknown: Determining what the question is asking.
Choosing the operation: Clearly identifying that subtraction is the correct mathematical operation to derive the answer.
Performing the calculation: Using the correct subtraction techniques to find the solution.
Writing the solution: Expressing the answer in correct units (e.g., 5 apples) and including a clear and concise explanation of the steps in the problem-solving process, avoiding vague descriptions such as simply stating the answer.
Example Word Problem:*

"Maria had 12 cookies. She gave 5 cookies to her friend. How many cookies does Maria have left?"