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Using Numbers.

When using numbers in essays and reports, it is important to decide whether to write the number out in full (two hundred thousand four hundred and six) or to use numerals (200,406).

There are some rules to follow to make sure you use numbers in the right way.

Use words if the number can be written in two words of fewer. Remember that some words require a hyphen (twenty-six, thirty-nine). Some guides recommend that numbers up to nine should be written in words, and those over nine written using numerals.

You should use numerals if the number modifies a unit of measurement, time or proportion (5 minutes, 8 kilograms, 54 mph). Abbreviations of units of measure should always be in the singular. (8 kg, 17cm, 12,900 km)

I live at number forty-eight.

I thought there were nine biscuits left in the tin?

My new car does 0-60 mph in just over 12 minutes.

She broke the long jump record by 17 centimetres.

The prize marrow weighed over 67 kg.

Numerals should be used for all larger numbers although the context might determine the precise usage. In technical writing such numbers should always be written using numerals. If the number is less precise, it may be possible to write the number in words.

The rock sample measured 17.74 grams when dried.

The lower attaining maths group's mean score was 88.6, with a standard deviation of 14.3.

There are over thirty million people living in Mexico City.

Florida contains several thousand disenfranchised voters.

Numerals should always be used for decimals and fractions (7.625, 1/4 in, 1/2 a pint, 0.75) unless the figures are vague (...half the voters in the country..., ...two thirds of the population cannot use a colon correctly.)

Following the drying process, 1/2 a gram of copper sulphate was added.

Students spend more than half their disposable income on baked beans.

She beat the world pole-vault record by 1/4 cm.

Nearly a quarter of the world's population survives on less than a pound a day.

Place a hyphen after a unit of measure when the unit modifies a noun: 10-foot pole, 6-inch rule, 3-year-old horse.

He tried to retrieve the lost bottle with a 5-foot stick.

I teach a class of angelic 7-year-old children.

The thief was unable to scale the 12-metre fence.

He was delighted with his 78-kg prize marrow.

There are occasions where combining written numbers and numerals will clear up possible confusion. Where you have two numbers running together, write the shorter one out in words and use numerals for the longer one.

I have a lovely class of 32seven-year-old children.

We need another 12five-litre bottles.

The thief made off with twenty1000-dollar bills.

He counted out 200 fifty-pence pieces.

You should avoid beginning a sentence with a number that is not written out. If a sentence begins with a year, write 'The year' before writing out the year in numbers.

One hundred and seventeen protests were lodged with the ombudsman.

Six hundred and thirty-five nuggets were discovered in the first day of the gold rush.

The year 1849 saw the great gold rush in California.

You should always use numerals in the following situations:

With dates. Monday 20 April, 1968.

I will arrive on Tuesday 17 May, 2004.

They are due back from their holiday on Monday 23 June.

With fractions, decimals and percentages. The word 'percent' should be written out in words unless it is part of a technical report, in which case it is fine to use the mathematical symbol (%).

You will need to add 1/2 a teaspoon of treacle.

More than 20 percent of students admit to spending more on pot noodles than on books.

The IQ scores of the children in the control group increased by 25.75 points.

With money. The only exception to this is when the amounts are vague. In such cases it is fine to write the numbers out in words.

The concert tickets cost £ 27.50 each.

Consumers spend over £ 6 million a year on cous-cous.

Global ice-cream sales exceeded $ 1.2 million last month.

With times. Again, if timings are vague it is fine to write them out in words.

The plane from Bombay will arrive at 16:45.

I'll see you at around half past seven.

The early morning bus arrived at 05:10 on the dot.

We left the pub at around eight o'clock and got home at around nine.

Test your understanding of the use of numbers with this exercise.