 Basic Maths For Dummies Cheat Sheet (UK Edition) - dummies

Basic Maths For Dummies Cheat Sheet (UK Edition)

Don’t let the thought of solving sums give you nightmares. This Cheat Sheet gives you some definitions and quick tips for improving your maths skills to make you feel more confident in no time.

Using the Table of Joy to Help with Maths Problems

With many sums, you can break them down into a grid to make it easier to work out the answer you need. Here are the steps for doing a sum using the Table of Joy:

1. Draw a noughts-and-crosses grid. It needs to be big enough so you can write labels in the rows and columns.

2. Label the rows and columns with the names of relevant information from the question.

3. Fill in the numbers relevant to each row and column, with a question mark for the square representing the answer you want.

4. Circle the number in the same column as the question mark and the number in the same row as the question mark. Write these numbers with a times sign between them. Then write a divide sign followed by the remaining number.

5. Work out the answer to the sum!

Shapes, Space and Measures Vocabulary

Part of making maths easier to understand is explaining what the different terms mean. Here’s a jargon-busting guide to help you along with maths questions involving shapes, space and measures.

• Acute angle: An angle smaller than a right-angle – so less than 90 degrees.

• Angle: The sharpness of a corner, measured in degrees. If you turn all the way around to face the way you started, you move through 360 degrees.

• Area: How much of something, such as paper, you need to cover a surface. You use different formulas to work out area for different shapes. You measure area in centimetres squared (cm2), or metres squared (m2) or any other unit of length squared.

• Capacity: How much space there is inside a shape.

• Circle: This is the only curved shape you really need to know about. The technical definition is ‘a shape with all of the points a fixed distance from the centre’, but you’ll recognise a circle when you see one.

• Cube: The shape of a normal die. Each of a cube’s sides is a square, and all of the edges are the same length.

• Cuboid: The shape of a shoebox. Each of its sides is a rectangle.

• Distance: How far one thing is from another. You measure distance in units of length, such as centimetres, metres, feet or inches.

• Length: How long an object is. You normally measure length in centimetres, metres, feet or inches.

• Obtuse angle: An angle that’s more than 90 degrees but less than 180.

• Perimeter: How far around a shape is – that is, if you walked all the way around a shape, how far you would travel. You measure perimeter in units of length, such as centimetres, metres, feet or inches. You find the answer by adding up the length of all of a shape’s sides.

• Pyramid: The shape of . . . well, guess! It has a square on the bottom and four identical triangles around the side that come together and meet at the top.

• Rectangle: A shape with four straight sides at right-angles to each other. The sides aren’t necessarily all the same length, but sides opposite each other are always the same length.

• Reflection: Turning a shape over.

• Reflex angle: An angle bigger than 180 degrees.

• Regular: A regular shape is one where all the sides are the same length and all the corners have the same angle.

• Right-angle: A quarter-turn, or 90 degrees.

• Rotation: Twisting a shape around its centre.

• Sphere: The shape of a ball.

• Square: A shape with four equal-length straight sides arranged at right-angles to each other. Again, you’ll probably recognise a square when you see one!

• Symmetry: A symmetrical shape is one you can either fold precisely in half, or twist around its centre so you can’t tell which way up it is.

• Temperature: How hot (or cold) something is, normally measured in degrees Celsius.

• Tessellation: Putting identical shapes together to make a pattern, with no spaces between the shapes.

• Triangle: Yes, you guessed it, a shape with three straight sides.

• Volume: How much space a shape takes up in three dimensions (3D).

• Weight: How heavy something is, normally measured in kilograms or grams.

Shedding Light on Graphs and Statistics Vocabulary

Don’t be scared or put off by intimidating terms to do with graphs and statistics. Following is a list of jargon that should shed some light on for you:

• Bar chart: A graph that looks like a city skyline – the height of each bar tells you how many things it represents.

• Line graph: Surprise! A graph with a line on it. How high the line is tells you what value the graph has at that point.

• Mean: The number you get by adding up a list of numbers and dividing by how many numbers there are.

• Median: The middle value in a list.

• Mode: The most common number in a list.

• Pictogram: A graph made of pictures. It works just like a bar chart.

• Pie chart: A circular graph divided into slices. The angle in each slice tells you what proportion of the total it represents.

• Range: The difference between the biggest and smallest number in a list.

• Scatter graph: A graph made up of crosses all over the place – each cross represents an observation, and the numbers on the two axes give its value.

• Tally chart: A table with short vertical lines grouped in sets of five (four lines with one line through them) to make them easier to count.