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B. Number · Operations: Numbers to 10 000, Decimal Tenths, Multiplying and Dividing

Operations: Numbers to 10 000, Decimal Tenths, Multiplying and Dividing: Unit Review

A1 B2.1 B2.2 B2.3 B2.4 B2.5 B2.6 B2.7 B2.8About 40 minutes
Learning goals
  • I can use properties of operations and recall multiplication and division facts to 10 × 10.
  • I can add and subtract whole numbers to 10 000 and decimal tenths, and check my answers.
  • I can multiply and divide 2- and 3-digit numbers by 1-digit numbers, and handle remainders.
  • I can multiply a unit fraction by a whole number, use rates, and solve multi-step problems.

Words to know

product
The answer when you multiply.
quotient
The answer when you divide.
remainder
What is left over when a number can't be divided equally.
regroup
Trade 10 of one place for 1 of the next place, or 1 for 10 going the other way.
partial products
The parts of a multiplication that you add together, like 6 × 40 and 6 × 7 for 6 × 47.
unit fraction
A fraction with 1 on top, like 1/4.
rate
A comparison of two different things, like 5 km per hour.

Let's review!

In this unit you became a much more powerful math thinker. You used the rules of operations, learned all your multiplication and division facts to 10 × 10, did mental math with 10, 100, 1000 and tenths, added and subtracted big numbers and decimals, multiplied and divided by 1-digit numbers, dealt with remainders, solved multi-step problems, multiplied unit fractions and used rates. This review has a few questions from every lesson. Try each one, then press Show answer to check. If a part feels tricky, go back to that lesson for more practice.

6 in each row4 rows4 × 6 = 246 × 4 = 2424 ÷ 4 = 624 ÷ 6 = 4
Quick recap: 4 rows of 6 make 24. One array shows a whole fact family, two multiplication facts and two division facts.
+Addin all, totalaltogetherhow many now?−Subtracthow many left?how many more?difference×Multiplyequal groups ofper, eachtimes as many÷Divideshare equallyhow many groups?how many each?
Quick recap: words that often point to each operation. Clue words are only hints, so always picture the story and check that your answer makes sense.

Math Rules: Properties of Operations

1

0 + 586 = ? and 586 × 1 = ?

2

35 + 78 + 65 = ?

3

8 × 16 = ? Split 16 into 10 + 6.

Multiplication Facts to 10 × 10

1

6 × 8 = ?

2

9 × 7 = ?

3

4 × 7 = ?

4

7 × 7 = ?

Division Facts and Fact Families

1

63 ÷ 7 = ?

2

48 ÷ 8 = ?

3

Write the fact family for 4, 9 and 36.

Mental Math: Multiplying by 10, 100 and 1000, Dividing by 10

1

46 × 100 = ?

2

7 × 400 = ?

3

5300 ÷ 10 = ?

Mental Math: Adding and Subtracting Tenths

1

0.7 + 0.8 = ?

2

3.9 + 2.4 = ?

3

5.1 − 4.7 = ?

Adding Whole Numbers to 10 000

1

3546 + 2738 = ?

2

Estimate 4120 + 2890.

3

A town recycled 2785 kg of paper in spring and 3460 kg in fall. How much in all?

Subtracting Whole Numbers within 10 000

1

8264 − 3519 = ?

2

7000 − 2468 = ?

3

Check 5310 − 1875 = 3435 with addition.

Adding and Subtracting Decimal Tenths

1

16.4 + 8.9 = ?

2

20 − 7.3 = ?

3

It snowed 14.5 cm on Friday and 9.8 cm on Saturday. How much more fell on Friday?

Multiplying 2- and 3-Digit Numbers by 1-Digit Numbers

1

7 × 36 = ?

2

4 × 237 = ?

3

A theatre has 9 rows of 28 seats. How many seats?

Dividing 2- and 3-Digit Numbers by 1-Digit Numbers

1

78 ÷ 3 = ?

2

344 ÷ 8 = ?

3

525 hockey cards are shared equally by 5 friends. How many each?

Division with Remainders

1

58 ÷ 6 = ?

2

35 skiers ride a chairlift. Each chair holds 4 people. How many chairs are needed?

3

7 pizzas are shared equally by 4 families. How much does each family get?

Solving Multi-Step Problems and Checking Answers

1

Jo buys 3 packs of 12 pencils and gives away 8. How many does she have?

2

A family has $300. They buy 4 tickets for $45 each. How much is left?

3

I think of a number. I multiply it by 4 and add 7. I get 39. What's my number?

Repeated Addition of Unit Fractions: Multiplying a Fraction by a Whole Number

1

Write 1/8 + 1/8 + 1/8 as a multiplication. Solve it.

2

5 × 1/2 = ?

3

8 × 1/4 = ?

Rates: Multiplicative Relationships

1

A bike has 2 wheels. How many wheels on 9 bikes?

2

Lia reads 25 pages per day. How many pages in 4 days?

3

Pens cost $3 each. How many pens can you buy with $27?

Just for fun

Q: Why did the multiplication table go to the gym?

A: To work on its 6s... and its 7s, 8s and 9s!

How to use this review

  • Do the review over two or three short sittings. Each section matches one lesson.
  • Estimate first for adding, subtracting, multiplying and dividing questions, then check that your answer is close.
  • Use tools if you need them: grid paper, bundles of sticks, dimes and loonies, measuring cups or a number line. Using tools is part of Grade 4 math.
  • Check with the partner operation: addition for subtraction, multiplication for division.
  • Put a star next to any question you got wrong, and go back to that lesson's practice.
Check your understanding

Quiz

1.

What is 4 × 19 × 25?

2.

What is 8 × 7?

3.

What is 54 ÷ 6?

4.

What is 38 × 100?

5.

What is 0.9 + 0.6?

6.

What is 5627 + 2845?

7.

What is 6000 − 3724?

8.

What is 6 × 58?

9.

30 children go skating. Each van holds 7. How many vans are needed?

10.

What is 3 × 1/5?

For parents and teachers

Use mistakes to choose what to revisit. Each review section matches one lesson.

  • Uses "any order" for subtraction, or forgets to add the parts after splitting: revisit Math Rules: Properties of Operations.
  • Slow or unsure with 3s, 4s, 6s, 7s, 8s or 9s facts: revisit Multiplication Facts to 10 × 10 and play multiplication war daily.
  • Can't turn a division into a multiplication, or writes division backwards: revisit Division Facts and Fact Families.
  • Wrong number of zeros (7 × 400 = 280), or shifts digits the wrong way when dividing by 10: revisit Mental Math: Multiplying by 10, 100 and 1000, Dividing by 10.
  • Writes 0.7 + 0.8 = 0.15, or fixes a friendly number the wrong way: revisit Mental Math: Adding and Subtracting Tenths with dimes and loonies.
  • Forgets to carry, or misaligns digits in 4-digit sums: revisit Adding Whole Numbers to 10 000.
  • Takes the smaller digit from the bigger one, or gets stuck with zeros (7000 − 2468): revisit Subtracting Whole Numbers within 10 000.
  • Lines up last digits instead of decimal points, or loses the decimal point: revisit Adding and Subtracting Decimal Tenths.
  • Multiplies only the ones, or forgets a partial product: revisit Multiplying 2- and 3-Digit Numbers by 1-Digit Numbers and draw area models.
  • Doesn't trade a leftover ten, or forgets to add up the groups: revisit Dividing 2- and 3-Digit Numbers by 1-Digit Numbers with bundles of sticks.
  • Remainder bigger than the divisor, or doesn't round up when everyone needs a seat: revisit Division with Remainders.
  • Stops after one step, or adds every number in a story: revisit Solving Multi-Step Problems and Checking Answers and draw bar models.
  • Multiplies the denominator too (3 × 1/5 = 3/15): revisit Repeated Addition of Unit Fractions: Multiplying a Fraction by a Whole Number with measuring cups or paper strips.
  • Adds instead of multiplying in a rate (9 bikes have 11 wheels), or can't tell when to divide: revisit Rates: Multiplicative Relationships and make a table.

A few mistakes are normal. Praise the strategy your child explains, not only the right answer.