NB Grade 5 Math key terms

The value a digit has because of its position in a number. In 4,382 the 3 means 300, the 8 means 80, and the 4 means 4,000.

A number written with digits in the usual way, one digit per place. The standard form of three thousand forty-six is 3046.

A number broken apart to show the value of each digit added together. 5,207 in expanded form is 5,000 + 200 + 7.

A number written out in words rather than digits. The word form of 812 is eight hundred twelve.

Replacing a number with a nearby number of a chosen place value. Look at the digit to the right: 4 or less keeps the place, 5 or more raises it by one.

Finding an answer that is close enough rather than exact, often by rounding or using friendly numbers. Estimation helps check whether a calculated answer is reasonable.

Numbers adjusted to friendly values that are easy to compute with mentally. To estimate 612 ÷ 6, use 600 ÷ 6 = 100.

A whole number that divides another number with no remainder. The factors of 12 are 1, 2, 3, 4, 6, and 12.

The result of multiplying a number by a whole number. The multiples of 4 include 4, 8, 12, 16, and 20.

A whole number greater than 1 with exactly two factors, 1 and itself. Examples are 2, 3, 5, 7, and 11.

A whole number greater than 1 that has more than two factors. Since 12 has six factors, it is composite.

The smallest number that is a multiple of two or more given numbers. The least common multiple of 4 and 6 is 12.

The largest number that divides two or more given numbers with no remainder. The greatest common factor of 18 and 24 is 6.

Different fractions that name the same amount of a whole. One half equals two fourths and five tenths.

A fraction written with the smallest possible whole-number numerator and denominator. Twelve eighteenths in simplest form is two thirds.

A number that is a multiple of the denominators of two or more fractions, allowing them to be added or compared. For sixths and fourths, 12 works.

A fraction whose numerator is greater than or equal to its denominator, so it names one whole or more. Seven fourths is improper.

A number made of a whole number and a proper fraction together. Two and three quarters is a mixed number.

A number written with a decimal point to show tenths, hundredths, and smaller parts of a whole. 0.75 means seventy-five hundredths.

A part out of one hundred, written with the percent symbol. 40% means 40 out of every 100, or four tenths.

A description of how each term in a sequence is made from the one before it. In 3, 7, 11, 15 the rule is add 4.

An ordered list of numbers or shapes that follows a rule. 2, 4, 8, 16 is a sequence in which each term doubles.

One number or shape in a sequence, identified by its position. In 5, 10, 15, 20 the third term is 15.

A pattern in which each new term is built from the term or terms just before it. Growing by adding 3 each time is recursive.

A mathematical phrase using numbers, operations, and sometimes letters, but no equals sign. Three times a number plus two is an expression.

A letter or symbol that stands for an unknown or changing number. In n + 5, the letter n is a variable.

A mathematical sentence stating that two expressions have the same value, joined by an equals sign. 4 × 6 = 24 is an equation.

The agreed order for calculating an expression: work inside brackets first, then multiply and divide left to right, then add and subtract left to right.

The distance all the way around the outside of a shape. Add the side lengths of a rectangle to find its perimeter.

The amount of surface a shape covers, measured in square units. A rectangle 4 cm by 3 cm has an area of 12 square centimetres.

The amount of space a solid figure takes up, measured in cubic units. It is found by multiplying length, width, and height.

A unit of area equal to a square one unit on each side, such as one square centimetre. Areas are counted or calculated in square units.

A unit of volume equal to a cube one unit on each edge, such as one cubic centimetre. Volumes are reported in cubic units.

A solid box shape with six rectangular faces. Its volume equals length times width times height.

The figure formed by two rays meeting at a shared endpoint called the vertex. Angles are measured in degrees.

An angle that measures more than 0 degrees and less than 90 degrees. It looks narrower than a square corner.

An angle that measures more than 90 degrees and less than 180 degrees. It looks wider than a square corner.

An angle that measures exactly 90 degrees, forming a square corner. The corners of a rectangle are right angles.

A measuring tool marked in degrees, used to find the size of an angle. Its straight edge is lined up with one ray at the vertex.

A line that divides a shape into two halves that match exactly when folded along it. A square has four lines of symmetry.

Having exactly the same size and shape. Two figures are congruent if one fits exactly on the other.

A flip of a shape over a line so it faces the opposite way. The flipped image is the same size and shape as the original.

Facts or numbers collected to answer a question, such as the number of books each student read. Data can be organised in tables and graphs.

A table that records how often each value or category occurs. Tallies or counts are grouped by category to show how many times each appears.

A graph that uses bars of equal width to compare amounts in different categories. The height or length of each bar shows the count.

A graph that plots points and joins them with line segments to show how a value changes over time.

The numbers and spacing used along a graph's axis to show how much each step represents. A scale of 2 means each grid line counts as two.

One of the two numbered lines that frame a graph. The horizontal axis often names categories and the vertical axis shows amounts.

The average of a set of numbers, found by adding all the values and dividing by how many there are. The mean of 4, 6, and 8 is 6.

The middle value when a set of numbers is arranged in order. With an even count, it is the mean of the two middle values.

The value that appears most often in a set of data. In 3, 5, 5, 7, 9 the mode is 5.

The difference between the greatest and least values in a data set. For 12, 15, 20, and 31 the range is 19.

A number from 0 to 1 describing how likely an event is. Zero means impossible, one means certain, and one half means equally likely.

One possible result of an experiment or chance event. Rolling a 4 on a number cube is a single outcome.

A planned activity that is repeated to collect results, such as spinning a spinner many times and recording where it stops.

Judging whether an answer makes sense in the situation by checking its size, units, and how it was found. Estimation is a common way to test reasonableness.

A planned approach used to tackle a question, such as drawing a diagram, making a table, working backwards, or guessing and checking.