## Activity 50

Evaluate 3 Ã· Author(s): The Open University

## Activity 46

Evaluate each of the following.

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## Activity 44

Is the following statement true or false?

Adding the same number to the top and bottom of a fraction gives you an equivalent fraction.

Addition and subtraction with fractions can be quite awkward, particularly when fractions are mixed with whole numbers and when the fractions have different denominators. In such cases you may need to use your calculator. However try to gain confidence in handling simple fractions.

To add two fractions with the same denominator, just add the numerators. For example,

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## Activity 40

Without using your calculator, find the following.

• (a) 75.6 Ã· 0.6

• (b) 75.6 Ã— 0.6

• (c) 100.001 + 75.6 Ã· 0.6

• (d) (100.
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The same rules about the order of calculations apply to decimals as apply to whole numbers.

## Calculations are performed in the following order:

Brackets;

Powers (e.g. squaring or cubing a number);

Division and Multiplication (performed in the order written, left to
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## Activity 36

Without using your calculator, find the following:

• (a) 100.001 + 10.1

• (b) 100.001 âˆ’ 10.1

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## Activity 28

Look at the rules in the boxes above.

Write in your own words the rules for multiplying and dividing, adding and subtracting two numbers, giving an example of each.

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## Example 7

Imagine a friend is planning a new kitchen in her house. In the kitchen showroom she noticed that the measurements of most of the kitchen units were given in millimetres. One worktop, for instance, is 575 mm deep. What units should she use to measure the large room in the
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It is worth mentioning notation at this point. You may have noticed that the minus sign used to denote a negative number is shorter, closer to the number and raised, compared with the minus sign used to denote subtraction. It is important to distinguish between the two, and it can help to think of âˆ’3, say, as â€˜negative 3â€™ rather than â€˜minus 3â€™. In the calculation 8 âˆ’ 3 (8 subtract 3), the minus sign is an operator, an instruction to subtract; in âˆ’3,
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## Activity 9

The diagram below shows an oatmeal cake marked into 12 equal portions. I want to give my sister a third of the cake. Where could I cut the cake, and what would be left over?

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After studying this course, you should be able to:

• write whole numbers and decimals in place-value columns and compare their sizes

• multiply and divide whole numbers and decimals by 10, 100, 1000 and so on

• indicate given fractions on a diagram and find equivalent fractions for a given fraction

• mark numbers on a number line

• choose appropriate units for a given purpose.

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The content acknowledged below is Proprietary (see terms and conditions) and is made available under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 Licence

Grateful acknowledgement is made to the following sources for permission to reproduce material in this course:<
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## Study another free course

There are more thanÂ 800 coursesÂ on OpenLearnÂ for you to
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Up to now only those points with positive or zero coordinates have been considered. But the system can be made to cope with points involving negative coordinates, such as (âˆ’2, 3) or (âˆ’2, âˆ’3). Just as a number line can be extended to deal with negative numbers, the x-axis and y-axis can be extended to deal with negative coordinates.

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## Activity 16

Write down the coordinates of A and B.

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## Activity 10

This table categorises Tom's activities for the day.

Activity<
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## Activity 7

Tables often give information in percentages. The table below indicates how the size of households in Great Britain changed over a period of nearly 30 years.

Number of people in household1961 (%)1971 (%)1981 (%)1991 (%)
1Author(s): The Open University

## Activity 6

The table below indicates the cooling rate of tea in a teapot.