Numerical expression: A mathematical phrase that uses numbers and operation symbols (+, -, ×, ÷) to represent a calculation.
• Keywords for addition: "more", "total", "altogether", "sum", "increased by", "combined"
• Structure: Starting amount + Added amount
• No equals sign: An expression shows the calculation, not the result
15 + 8
• Keywords for subtraction: "gave", "left", "remaining", "difference", "decreased by", "less than"
• Structure: Starting amount - Amount taken away
• Order matters: The first number is always the starting amount
24 - 9
• Keywords for multiplication: "each", "per", "times", "groups of", "product", "multiplied by"
• Structure: Number of groups × Items per group
• Equal groups: Multiplication represents repeated addition of equal groups
6 × 12
Numerical expression: A combination of numbers and operation symbols that shows a calculation without solving it.
Operation: A mathematical action (addition, subtraction, multiplication, division).
Variable: A symbol (usually a letter) that represents an unknown number (not used in 4th grade).
- Read carefully: Understand what the problem is asking
- Find key information: Identify the numbers and important details
- Look for operation words: Find words that indicate the operation needed
- Identify the order: Determine which number comes first
- Write the expression: Put the numbers and operation symbol together
• No equals sign: Numerical expressions don't have equals signs or answers
• Operation words: Learn to recognize key words that indicate operations
• Context matters: Make sure your expression fits the story
• Number order: Pay attention to which number comes first in subtraction/division
• Keywords for division: "share equally", "divide", "per", "split", "groups of", "how many in each"
• Structure: Total amount ÷ Number of groups
• Equal sharing: Division represents fair sharing into equal groups
36 ÷ 4
• Multi-step problems: May require more than one operation
• Parentheses: Show which operation should be done first
• Order of operations: Multiplication/division before addition/subtraction
(5 × 8) - 12
Numerical expression: A mathematical phrase containing numbers and operation symbols (+, -, ×, ÷) without an equals sign.
Operation: A mathematical action that combines numbers (addition, subtraction, multiplication, division).
Term: Each number in an expression (in 3 + 5, the terms are 3 and 5).
Result: The answer when you evaluate (solve) an expression.
- Read the entire problem to understand the situation
- Identify and circle all numbers in the problem
- Look for operation clue words that indicate the operation needed
- Determine the order of numbers (especially important for subtraction and division)
- Write the numerical expression using numbers and operation symbols
- Check if your expression makes sense in the context of the problem
• Addition words: more, total, altogether, sum, increased by, combined, plus
• Subtraction words: less, fewer, left, remaining, difference, decreased by, take away
• Multiplication words: each, per, times, groups of, product, multiplied by, rows of
• Division words: share equally, divide, per, split, how many in each, distributed
• Order matters: In subtraction and division, the order of numbers affects the result