Primary 3 Mathematics

A number from 1000 to 9999, made of four digits.

The 4th place from the right; each 1 means 1000.

The 3rd place from the right; each 1 means 100.

The 2nd place from the right; each 1 means 10.

The 1st place from the right; it counts ones.

The value a digit has depends on its position.

Writing a number stretched out, e.g. 3456 = 3000 + 400 + 50 + 6.

To see which number is bigger or smaller.

A symbol 0-9 used to write numbers.

Putting numbers together, e.g. 1234 + 567.

Taking part of a number away, e.g. 3000 - 1234.

Writing numbers in vertical columns to calculate.

Line up ones with ones, tens with tens.

In addition, when a place fills 10, send 1 to the next place left.

In subtraction, borrow 1 (which is 10) from the next place left.

The answer to an addition, e.g. the sum of 1234 + 567 is 1801.

The answer to a subtraction, e.g. the difference of 3000 - 1234 is 1766.

A quick way to add equal groups, e.g. 3×4 = 3+3+3+3.

The answer to a multiplication, e.g. the product of 3×4 is 12.

A table of one number times 1, 2, 3…, e.g. the 3 times table: 3, 6, 9…

Adding the same number many times, e.g. 4+4+4 = 3×4.

Groups with the same amount, e.g. 3 bags of 4 oranges each.

Objects arranged in neat rows and columns to show multiplication.

The numbers being multiplied, e.g. 3 and 4 in 3×4.

Counting by adding the same number each time, e.g. 3, 6, 9, 12.

Sharing equally, e.g. 12÷3 means sharing 12 sweets among 3 people.

The total being shared, e.g. the 7 in 7÷3.

The number of groups or the size per group, e.g. the 3 in 7÷3.

The answer of a division, e.g. in 7÷3 = 2 R1 the quotient is 2.

What is left over when sharing is not exact, e.g. 7÷3 leaves remainder 1.

Everyone or every group gets the same amount.

What remains when it is too few to share again.

Use quotient × divisor + remainder to see if it equals the dividend.

A number showing parts of an equally divided whole, e.g. 14.

The top number of a fraction; it tells how many parts are taken.

The bottom number of a fraction; it tells how many equal parts the whole has.

The complete object before cutting, e.g. a whole apple.

Parts of the same size; fractions only work with equal sharing.

One part out of 2 equal parts.

One part out of 4 equal parts.

Say the denominator first: 34 reads three quarters.

5, 10, 15, 20… add 5 each time; answers end in 0 or 5.

6, 12, 18, 24… add 6 each time.

The answer to a multiplication, e.g. 5×7 = 35.

Counting by adding the same number each time.

Counting coins worth 5 is counting the 5 times table.

5×n is half of 10×n, e.g. 5×8 = 40 = half of 80.

6×n is double 3×n, e.g. 6×4 = 24 = 12 doubled.

A maths question in story form, solved with times tables.

7, 14, 21, 28… add 7 each time.

8, 16, 24, 32… add 8 each time.

The answer to a multiplication, e.g. 7×8 = 56.

8×7 equals 7×8; knowing one gives you both.

8×n doubles n three times: 4 → 8 → 16 → 32.

Facts people mix up, e.g. 7×8 = 56 (not 54).

Counting by adding the same number each time.

A week has 7 days — counting weeks is the 7 times table.

Fractions with the same bottom number, e.g. 15 and 25.

The top number; adding and subtracting happen here.

The bottom number; it stays the same in same-denominator sums.

Keep the denominator, add numerators: 15 + 25 = 35.

Keep the denominator, subtract numerators: 47 − 17 = 37.

A fraction with numerator 1, the building block, e.g. 18.

Numerator equals denominator means the whole: 88 = 1.

The whole minus what is taken, e.g. 1 − 38 = 58.

A number with a decimal point showing parts of one, e.g. 0.5.

The dot separating whole parts from fraction parts.

The first place after the point; 0.1 is one tenth.

The second place after the point; 0.01 is one hundredth.

One part of 10 equal parts of a whole, written 0.1.

Five tenths, 510, which is one half.

$1.5 means 1 dollar 50 cents; the first decimal place is dimes/tenths.

0.3 reads zero point three; the dot reads point.

A solid with two equal circular faces, e.g. a can.

A solid with one circular face and one apex, e.g. a traffic cone.

A flat or curved surface of a solid.

A rounded surface, e.g. the side of a cylinder.

A flat circle; a cylinder has two, a cone has one.

The sharp point at the top of a cone.

The line where two faces meet, e.g. the rim of a cylinder.

Curved surfaces let solids roll, e.g. a can on its side.

The opening formed by two lines meeting at a point.

Seeing which angle opens wider.

How far the two sides of an angle spread apart; it decides the angle size.

The point where the two sides of an angle meet.

The two lines that make the angle.

The one with the wider opening, no matter the side lengths.

A corner folded from paper, used to overlay and compare angles.

Clock hands make angles, e.g. a right angle at 3 o'clock.

Two lines going the same way that never meet.

Two lines that meet at a right angle (90°).

Two lines crossing each other.

A 90° angle, square like the corner of a book.

The classic parallel example: two rails that never meet.

The classic perpendicular example: horizontal and vertical meeting at right angles.

A triangle tool with a right angle, used to draw or check perpendicular lines.

In a rectangle, opposite sides are parallel; neighbouring sides are perpendicular.

A flat shape with 3 sides and 3 angles.

A straight line of the shape; a triangle has 3.

The opening where two sides meet; a triangle has 3.

The point where two sides meet; a triangle has 3.

A triangular tool with a right angle, used for drawing.

A shape with no gaps; the 3 sides must close up.

A triangle whose 3 sides are all the same length.

A triangle with one 90° angle, like a set square.

An angle smaller than 90°, sharp-looking.

An angle of exactly 90°, like a book corner.

An angle bigger than 90° but under 180°, wide open.

The unit for angles; a right angle = 90°.

Use the set square's right angle as the standard to compare.

2 o'clock shows an acute angle, 3 a right angle, 5 an obtuse angle.

A door ajar is acute, half open right, wider obtuse.

Classify angles by comparing with 90°: less, equal, more.

A quadrilateral with both pairs of opposite sides parallel.

A parallelogram with all 4 sides equal, like a diamond.

The non-neighbouring sides; in a parallelogram they are parallel and equal.

A closed shape with 4 sides.

Same direction, never meeting.

Sides of the same length; a rhombus has four of them.

Four equal sides with four right angles — a special rhombus.

A quadrilateral with two pairs of equal neighbouring sides — different from a rhombus.

The unit for long distances; 1 km = 1000 m.

The unit for everyday lengths; a door is about 2 m tall.

How far it is between two places.

The standard used to measure, e.g. m, km, cm.

Changing one unit to another, e.g. 3 km to 3000 m.

A very long way, e.g. from home to another district.

The loop at a sports ground; one lap is 400 m.

A sign showing how far the destination is, written in km.

The unit for heavy things; 1 kg = 1000 g.

The unit for light things; a sweet is about 5 g.

How heavy an object is.

A tool for measuring weight, found in markets and kitchens.

Changing between kg and g, e.g. 3 kg = 3000 g.

Weighing more, e.g. 5 kg is heavier than 3 kg.

Weighing less, e.g. 200 g is lighter than 500 g.

A tool that compares weights; the side that sinks is heavier.

How long something takes from start to end.

The time an event begins, e.g. 2:15.

The time an event finishes, e.g. 3:00.

The short hand; moving one number takes 1 hour.

The long hand; each number it passes is 5 minutes.

Counting forward from the start time to the end time.

The minute hand on 6, meaning 30 minutes past, e.g. 2:30.

The minute hand on 12, e.g. 3:00 reads three o'clock.

Counting 00:00 to 23:59, used in train timetables.

Splitting the day into a.m. and p.m.

From midnight to 11:59 am; written the same in 24-hour form, e.g. 9:00.

From noon to midnight; add 12 in 24-hour form, e.g. 3 pm = 15:00.

12:00, the divide between morning and afternoon.

00:00, the start of the day, written 00:00.

A list of times for trains or events, often in 24-hour form.

The rule for pm times: 3 + 12 = 15.

A tiny length unit; 1 cm = 10 mm.

The unit for short objects; 1 cm = 10 mm.

Each small mark is 1 mm; each numbered block is 1 cm.

The tiny marks between two numbers — count 10 of them.

How thick something is, e.g. a notebook about 5 mm.

Changing between cm and mm, e.g. 5 cm = 50 mm.

Coins are small and thin; their size is measured in mm.

More precise; mm makes measurements finer.

The big unit for liquid capacity; 1 L = 1000 mL.

The small unit for liquids; a toothpaste tube is about 100 mL.

How much liquid a container can hold.

A cup with scale marks for measuring mL.

Kettles are labelled in L, e.g. 1.7 L.

Changing between L and mL: 2 L = 2000 mL.

Bottles are labelled in mL, e.g. 500 mL.

Anything that holds liquid: cup, pot, bottle.

How much flat surface a shape covers.

The area of a 1 cm by 1 cm square; the unit of area.

Paper ruled into equal squares, used to count area.

A square completely inside the shape; counts as 1 unit.

A square half covered by the shape; two halves make 1.

The basic way to measure area: count the squares.

To tile the whole shape with unit squares.

Perimeter is the border length; area is the space inside — different things.

A chart that uses bars of different lengths to show amounts.

A bar in the chart; longer means a bigger amount.

The line lying flat; it shows categories, e.g. fruit names.

The upright line; it shows the counts, e.g. 5, 10, 15.

How much each gridline stands for, e.g. one square = 2.

The collected numbers, e.g. votes for favourite fruit.

The longest bar is the most; the shortest is the least.

Counting with stroke marks, five at a time.