21/5/18 The Difference between Amount, Quantity, and Number

Use amount of before singular things you cannot measure. For example:

  • A large amount of disdain

Use quantity of before a singular (and sometimes plural) thing you can measure, particularly if it’s inanimate. For example:

  • A large quantity of money

Use number of before plural things you can measure. For example:

  • A large number of coins

There are subtle differences between amount of, quantity of and number of.

Amount Of
The term amount of is used for things you cannot measure, i.e., non-countable nouns. Amount of usually precedes a singular word.
Examples:
I undertook an inordinate amount of work.
(Work is a non-countable noun. It is singular and cannot be measured or counted.)

  • She had a certain amount of respect for the sales team, but she always dissented when they spoke at meetings.

(Respect is singular and cannot be measured or counted.)

  • It is not difficult to see where that amount of hate derives.

(Hate is singular and cannot be measured or counted.)

  • The amount of women in London who flirt with their own husbands is perfectly scandalous. It looks so bad. It is simply washing one’s clean linen in public.  (Oscar Wilde)

(Women is plural and can be counted. This should be the number of women. )

Quantity Of
The term quantity of is used with singular or plural (but mostly singular) things that you can measure, i.e., countable nouns. It is usually applied to inanimate objects. (Some older grammar references might advocate that quantity of can only precede a singular word; however, this view is now considered outdated.)
Examples:

  • I took control of a large quantity of money.

(Money is singular and can be measured or counted.)

  • The ship was only carrying a large quantity of mangoes.

(Mangoes is plural, and they can be measured or counted.)
(Note: Number of could also be used in this example. In fact, number of is preferable as it is unlikely to be considered incorrect by those who don’t like to see quantity of with a plural noun.)

Number Of
The term number of precedes a plural, countable noun. It can be applied to both animate and inanimate objects.
Examples:

  • The disease affected a large number of camels in the town.

(Camels is plural and animate, and they can be counted.)

  • The ship was only carrying a large number of mangoes.

(Mangoes is plural and inanimate, and they can be counted.)
(Note: Quantity of could also be used in this example.)

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