Whole Numbers & Operations · Grades 3, 4
Times as Many: Comparison and Multi-Step Word Problems
Quick answer
A times-as-many comparison multiplies. Five times as many as 7 is 35. A more-than comparison adds, so 5 more than 7 is 12 — the same two numbers and a different question. Multi-step problems are handled the same way: write down what each step gives before moving on, so nothing has to be held in your head.
What you'll learn
- Read a times-as-many statement as a multiplication
- Tell a multiplying comparison from an adding one
- Solve a multi-step word problem one step at a time
Times as many means multiply
That can be read as a comparison:
- is five times as many as
- is seven times as many as
Both are true. The equation holds two comparisons at once, one for each factor.
Why “times as many” is not “more than”
These two phrases sound similar and do opposite things.
| Phrase | Operation | With and |
|---|---|---|
| more than | add | |
| times as many as | multiply |
Same two numbers. Answers that are nowhere near each other.
Look for the word “times”. It is the signal to multiply. Without it, phrases like more than, fewer than and increased by all mean adding or subtracting.
Finding how many times as many
Multiplication going one way means division coming back.
Ben has marbles. Amy has . How many times as many does Amy have?
Seven times as many.
This is the missing factor again: .
| Question | Operation |
|---|---|
| How many is times as many as ? | |
| is how many times as many as ? | |
| is times as many as what? |
Two-step problems
Most real problems need more than one step. The method is to finish one step and write the answer down before starting the next.
A store has boxes with pens in each. It sells pens. How many are left?
Step 1 — how many pens to start:
Step 2 — how many after selling:
Fifteen pens left.
Writing the down is the whole technique. Trying to hold it in your head while doing the next step is where most errors in these problems come from.
Writing it as one equation
The two steps can be joined into one statement, with a letter for the answer:
The parentheses keep the multiplication first, which the order of operations would do anyway — but writing them makes the intended order visible to a reader.
Checking the answer makes sense
An answer to a word problem describes something real, so it can be checked against the situation.
| Warning sign | What it usually means |
|---|---|
| bigger than the total | added where you should have taken away |
| a negative amount | subtracted the wrong way round |
| not a whole number of objects | multiplied or divided the wrong pair |
| far larger than expected | multiplied where you should have added |
In the pen problem, is less than the started with, which is right for a shop that sold some. An answer of would mean the store gained pens by selling them.
This check costs one sentence and catches the errors that matter.
Worked examples
Common mistakes
Practice problems
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What is times as many as ?
Answer
Full solution
“Times as many” multiplies: .
-
What is more than ?
Answer
Full solution
“More than” adds.
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is how many times as many as ?
Answer
Full solution
.
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A book costs dollars. A game costs times as much. What does the game cost?
Answer
dollars
Full solution
.
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There are bags with apples each. How many apples?
Answer
Full solution
.
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From those apples, are eaten. How many are left?
Answer
Full solution
.
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A tree is m tall. Another is times as tall. How tall is the second?
Answer
m
Full solution
.
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There are rows of chairs. chairs are taken away. How many are left?
Hint
Two steps. Write down the first answer.
Answer
Full solution
chairs to start.
left.
-
A pencil costs dollars. A pen costs . How many times as much is the pen?
Answer
times
Full solution
.
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A store has boxes of pens and sells . Asked how many are left, Tom answers . Find his error.
Hint
Should the store have more pens or fewer after selling?
Answer
He added instead of subtracting. The answer is .
Full solution
His first step is right: pens to start.
His second step added the instead of taking it away: .
Selling pens means having fewer, so the second step subtracts: .
The check catches this without redoing any arithmetic. An answer of is more than the the store started with, and a store cannot gain pens by selling them.
Frequently asked questions
What does times as many mean?
Multiply. Five times as many as 7 is 5 × 7 = 35.
How is that different from more than?
More than adds. 5 more than 7 is 12, while 5 times as many as 7 is 35. Same numbers, very different answers.
How do I find how many times as many?
Divide. If one is 35 and the other is 7, then 35 ÷ 7 = 5, so it is 5 times as many.
How do I handle a two-step problem?
Do one step, write down the answer, then start the next. Trying to hold a middle number in your head is where most errors come from.
How do I check a word problem answer?
Ask whether it makes sense. An answer bigger than the total, or a number of people that is not whole, means something went wrong.
Standards alignment
This lesson covers the following Common Core State Standards for Mathematics.
- CCSS.MATH.CONTENT.4.OA.A.1Operations and Algebraic ThinkingInterpret a multiplication equation as a comparison, e.g., interpret 35 = 5 × 7 as a statement that 35 is 5 times as many as 7 and 7 times as many as 5. Represent verbal statements of multiplicative comparisons as multiplication equations.
- CCSS.MATH.CONTENT.4.OA.A.2Operations and Algebraic ThinkingMultiply or divide to solve word problems involving multiplicative comparison, e.g., by using drawings and equations with a symbol for the unknown number to represent the problem, distinguishing multiplicative comparison from additive comparison.
- CCSS.MATH.CONTENT.4.OA.A.3Operations and Algebraic ThinkingSolve multistep word problems posed with whole numbers and having whole-number answers using the four operations, including problems in which remainders must be interpreted. Represent these problems using equations with a letter standing for the unknown quantity. Assess the reasonableness of answers using mental computation and estimation strategies including rounding.
- CCSS.MATH.CONTENT.3.OA.D.8Operations and Algebraic ThinkingSolve two-step word problems using the four operations. Represent these problems using equations with a letter standing for the unknown quantity. Assess the reasonableness of answers using mental computation and estimation strategies including rounding.