##### Document Text Contents

Page 2

DECIMALS: In Britain and the US, the decimal point is used to define a decimal

fraction. The point is used to separate the whole number from the fraction. In some

other countries, the comma is used to separate the whole number from the fraction.

FRACTIONS:

PERCENTAGES:

Here’s a little trick to make percentage calculations (without a calculator in Paper 1!)

easier:

x% of y = y% of x

Example:

8% of 50

8% of 50 is the same as 50% of 8

And 50% of 8 is 4

So 8% of 50 is 4

This blew my mind when I realised it!

Example:

Britain and US:

Other notation:

IB exams use the decimal point, not a comma.

4.

4,

It is easy to add fractions with the same denominator:

If the denominators are different, we somehow make them the same:

(In this example has an equivalent fraction of , which is the same denominator)

4

+

4

=

2

4

=

2

8

+

4

=

8

+

2

8

=

8

4

2

8

Find more great resources for IB Physics on:

aceyourphysicsexams.com

Page 6

DIRECT PROPORTION:

Two variables are in direct proportion if you draw a graph and it has a straight line

through the origin, like this:

INDIRECT PROPORTION:

Two variables are indirectly proportional if you draw a graph and looks like this:

Mathematically, you would express the relationship as:

It can also be expressed as:

Which is likened to the equation of a straight line ( ), where there is no y-

intercept.

α

=

y = m x + c

Find more great resources for IB Physics on:

aceyourphysicsexams.com

DECIMALS: In Britain and the US, the decimal point is used to define a decimal

fraction. The point is used to separate the whole number from the fraction. In some

other countries, the comma is used to separate the whole number from the fraction.

FRACTIONS:

PERCENTAGES:

Here’s a little trick to make percentage calculations (without a calculator in Paper 1!)

easier:

x% of y = y% of x

Example:

8% of 50

8% of 50 is the same as 50% of 8

And 50% of 8 is 4

So 8% of 50 is 4

This blew my mind when I realised it!

Example:

Britain and US:

Other notation:

IB exams use the decimal point, not a comma.

4.

4,

It is easy to add fractions with the same denominator:

If the denominators are different, we somehow make them the same:

(In this example has an equivalent fraction of , which is the same denominator)

4

+

4

=

2

4

=

2

8

+

4

=

8

+

2

8

=

8

4

2

8

Find more great resources for IB Physics on:

aceyourphysicsexams.com

Page 6

DIRECT PROPORTION:

Two variables are in direct proportion if you draw a graph and it has a straight line

through the origin, like this:

INDIRECT PROPORTION:

Two variables are indirectly proportional if you draw a graph and looks like this:

Mathematically, you would express the relationship as:

It can also be expressed as:

Which is likened to the equation of a straight line ( ), where there is no y-

intercept.

α

=

y = m x + c

Find more great resources for IB Physics on:

aceyourphysicsexams.com