Subtraction Word Problems Worksheets
How Do You Know When a Math Word Problem Requires Subtraction?
There are many different keywords or phrases that often indicate that subtraction is required to solve word problem. The keywords that often indicate this math operation are:
Difference – When the problem asks for the difference between two quantities or the amount by which one quantity is greater or smaller than another.
Example – Find the difference between 15 and 9.
Decrease – When the problem describes a reduction or decrease in a quantity.
Example – If you decrease a number by 7, what is the result?
Subtract – When the problem explicitly mentions the operation of subtraction.
Example – Subtract 5 from 12.
Take away – When the problem involves removing or subtracting a certain quantity from a total.
Example – If you take away 3 from 8, what remains?
Less – When the problem implies a comparison or a smaller value.
Example – John has $10 less than Sarah. If Sarah has $25, how much does John have?
Fewer – When the problem involves comparing the number of items or quantities and implies a smaller count.
Example – If there are 9 apples and 5 oranges, how many fewer oranges are there than apples?
Remaining – When the problem asks for the amount or quantity that is left after subtracting or removing a portion.
Example – If you have 15 cookies and eat 8, how many cookies are remaining?
How many more/less – When the problem asks for the difference in quantity between two numbers.
Example – Jane has 10 pencils, and Mark has 5 pencils. How many more pencils does Jane have than Mark?
Net – When the problem involves a calculation of the net result or the difference between two opposing quantities.
Example – If the sales revenue is $500 and the expenses are $300, what is the net profit?
These keywords or phrases often suggest a subtraction operation, but it’s important to carefully analyze the problem and understand the context to determine the appropriate mathematical operation to use.
In word problems, determining whether subtraction is required depends on the specific context and the relationship between the quantities mentioned in the problem. Here are some indications that a word problem might involve subtraction:
Comparison of quantities – If the problem involves comparing two or more quantities to find the difference between them, subtraction is often necessary. Phrases like “how much more/less,” “difference between,” or “subtracted from” often indicate subtraction.
Example – Mary has 15 apples, and John has 9 apples. How many more apples does Mary have than John?
Change or decrease in value – If the problem describes a change or decrease in a quantity over time or due to some action, subtraction might be involved. This could be indicated by terms such as “decrease,” “reduce,” “subtract,” or “take away.”
Example – Sarah had $50, and she spent $25 on a book. How much money does she have left?
Missing part or unknown quantity – If the problem presents a scenario where part of a whole is missing or unknown, subtraction can help find the missing value. This can be indicated by phrases like “how much is left,” “how many are missing,” or “what is the remaining amount.”
Example – A class had 30 students, and 17 students are present. How many students are absent?
Removing or separating items – If the problem involves removing or separating items from a group or a total, subtraction is often used to find the resulting quantity.
Example – There were 50 marbles in a bag, and 8 marbles were taken out. How many marbles are left in the bag?
Finding the complement – If the problem asks for the value that, when subtracted from another value, results in a given total, subtraction is required.
Example – If the sum of two numbers is 20, and one of the numbers is 14, what is the value of the other number?
It’s important to carefully read and understand the wording of the problem to identify the relationship between quantities and determine when subtraction is appropriate. In some cases, visualizing the problem or representing it with diagrams or equations can also help determine if subtraction is needed.