How to find a word in this dictionary
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Dictionary A-Z
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Maths Wizard Number and counting Addition and subtraction Mathematical symbols Multiplication and division Fractions, decimals and percentages Measurement Time Geometry Graphs, charts and diagrams
106 110 113 114 120 122 125 128 136
Acknowledgements
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How to find a word in this dictionary The words in a dictionary are listed in alphabetical order which makes it easy to find the word you are looking for.
beside bes s side
A
1 If you look at the words at the top of the page, this tells you what the first word is on a lefthand page, and what the last word is on a right-hand page. 2 To help you, the alphabet is shown down the side of each page. The coloured letter tells you what letter the words on that page start with.
B C
To be beside something is to be close to it or next to it. The triangle is beside the square.
D E F G
D See adjacent
H
between
I J K L M
3 The words you want to look up in the dictionary are bigger and printed in blue bold.
beside
N O P
If something is between two other things it iss in the space that separates them. A number between two others is bigger than one number and smaller than the other. The number 45 is between 44 and 46.
beyond To be beyond something is to be further than it or past it. If you choose a number beyond 10 000, it needs to be greater than 10 000.
Q
4 You can find a clear explanation of what the word means.
R S T U
5 Extra information about the word, or examples showing how it is used, are shown in the blue boxes.
V W X Y
billion A billion is one thousand million. It is written as 1 000 000 000. In the UK, a billion used to be a million million (1 000 000 000 000) but this is no longer in common use. Saturn is just under 1.5 billion kilometres from the sun.
D See giga-, million
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bisect bi sect To bisect is to divide a line, angle or area exactly in half. half This 60° angle is bisected into two angles c of 30°. 30° 30°
6 Some words have an illustration or photograph to help you understand the meaning.
divide, halve D See divide
block graph A block graph uses blocks to represent statistical data. Each block in a column or row represents p one object j or recording. g Favourite colours
D See bar chart -See Graphs, charts and diagrams in the Maths Wizard
brackets
7 The links to the Maths Wizard point you to where you can find lots more information on a range of mathematical terms and concepts. 8 There are suggestions for other words you might want to look up which are related to the word you are looking at.
Brackets are the symbols ( ). Brackets are used to put items or numbers together. In calculations, an operation within brackets is worked out before any other operations. 4 × (5 + 3) = 4 × 8 = 32 4 × 5 + 3 = 20 + 3 = 23
D See calculate, operation
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addend An addend is a number that is added to another number. 7 + 5 = 12 7 and 5 are both addends, with the sum of 12.
D See subtrahend, sum
addition (+) abacus (plural: abaci) An abacus is a simple calculating tool. Stones, beads or rings are used to count and calculate. This example has beads that slide along rods.
Addition is finding the total of two or more numbers. The + sign in a calculation shows that numbers are being added together. The addition of 12 and 7 gives 19. 12 + 7 = 19
D See sum, total -See Addition and subtraction in the Maths Wizard
adjacent Adjacent means near or next to something. In some countries abaci are still used to help calculate because they are quick to use. A suan pan is used in China and a soroban is used in Japan.
acute angle An acute angle is smaller than a right angle. It is an angle that is between 0° and 90°. D See obtuse angle, reflex angle, right angle, straight angle
In this set of number cards, 4 is adjacent to 9.
3 6 2 9 4 D See beside, opposite
adjust To adjust something means to change or alter it. If you adjust the scale it will change the shape of a graph.
-See Geometry in the Maths Wizard
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algebra g gebra
A B C D
algebra Algebra is a branch of mathematics that uses letters or symbols to represent numbers. It is used to help solve problems and investigate number patterns.
angle The amount by which something turns is an angle. It is a measure of rotation, measured in degrees (°).
The multiplication sign isn't used in algebra in case it is confused with the letter x. So 3 times n is written as 3n.
D See acute angle, degree, obtuse angle,
G
If y + 3 = 5, what is the value of y?
reflex angle, right angle, straight angle -See Geometry in the Maths Wizard
H
y=2
E F
I J K L M N
D See equation, formula -See Mathematical symbols in the
a.m. The short way of writing ‘ante meridiem’ is a.m., which means before midday or noon. The lessons started at 9.15 a.m.
O P
analogue clock
R
annual An annual event is one that happens once a year.
Maths Wizard
D See midday, p.m. -See Time in the Maths Wizard
Q
angle
Your birthday is an annual event. Unfortunately you can only celebrate it once a year.
anticlockwise When something turns anticlockwise, it goes round in the opposite direction to the hands on a clock.
An analogue clock measures time using hands moving around a dial.
S
D See clockwise, rotate
T
apex
U
The apex of a solid shape is the highest point from the base. The apex of a pyramid is the vertex at which the triangular faces meet.
V W X Y
vertex
D See digital clock, minute hand, secondd hand, time -See Time in the Maths Wizard
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D See pyramid, vertex
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array arr
approximate An approximate answer is very close to the right answer, but not exact. The sign ≈ means ‘is approximately equal to’. The approximate answer to 19 × 31 is 600. 19 × 31 ≈ 600
D See estimate, round
arithmetic Arithmetic is the branch of mathematics that involves numbers and calculating. It includes addition, subtraction, multiplication and division. Mental arithmetic is calculating in your head.
D See addition, division, multiplication, subtraction
arc
a
An arc is a curved line that would make a complete circle if you continued it. rc
A rainbow is an arc of colour in the sky.
array An array is a regular arrangement of numbers or objects. It has rows and columns, usually in the form of a rectangle. Arrays can help you work out a multiplication. This array shows that 3x4 is the same as 4x3 and they both equal 12.
D See chord, circle, circumference -See Geometry in the Maths Wizard
b c d e f g h i j k l m n o p
area The area of a surface is a measure of how much space is covered by that surface. It is usually measured in square units such as square centimetres (cm2) or square metres (m2)..
q r s
The area of a rectangle can be calculated by multiplying its length by its breadth (a = l x b). The area of this rectangle is 12 squares.
t D See multiplication -See Multiplication and division in the Maths Wizard
D See square centimetre, square metre
a
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arrowhead r rowhead
A B C
arrowhead An arrowhead is a quadrilateral with two pairs of equal sides and an angle greater than n 180°. It is sometimes called a dart.
average speed The average speed is found by dividing the total distance travelled by the total journey time. A car travels 150 km in 2 hours. Its average speed is 75 km/h.
D E
axis (plural: axes)
F G
D See quadrilateral, reflex angle
H
ascending
I J
Ascending means going up in order from smallest to largest.
K
The numbers 3.2, 2.5, 2.3 and 5.2 written in ascending order are:
L
2.3, 2.5, 3.2, 5.2
M
D See descending, order
N
average
O P Q R S T U V W X Y
The average of a group of numbers is a common (mode) or middle (median) value. The mean average of a set of numbers can be found by adding them and dividing the total by how many numbers there are. Hours of sunshine for five days
An axis is the horizontal or vertical line on a graph. The axes are used to measure the position of points on the graph. The x-axis is the horizontal axis and the y-axis is the vertical axis. y-axis
0
x-axis
D See coordinate, horizontal, vertical
axis of symmetry An axis of symmetry is a line about which a shape can be reflected and stay the same shape. A rectangle has 2 axes of symmetry.
Mon Tue Wed Thu Fri 6 4 9 6 10 Mode: 6 hours (two days with 6 hours) Median: 6 hours (4, 6, 6, 9, 10) Mean: 7 hours (6 + 4 + 9 + 6 + 10) ÷ 5 = 7
D See mean, median, mode
D See line symmetry, rotational symmetry -See Symmetry in the Maths Wizard
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