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Q: A: ### Quick Answer

**The number 90 is spelled "ninety."** It is formed from its base of nine followed by a -ty which signifies that the number is followed by a tens placeholder.

The number 90 is often misspelled because many people drop the "e" and leave the word as "ninty."

Numbers between 20 and 100 that are multiples of 10 are spelled from a form of the base number followed by the -ty: twenty, thirty, forty, fifty, sixty, seventy, eighty and ninety. For the numbers between them, simply append the spelled number in the ones place to the spelled number in the tens place. For example, to spell 47, simply add "seven" to the end of the spelled number forty to get "forty-seven."

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- Q:
## Is the number 1 prime or composite?

A:The number one is neither prime nor composite. Prime numbers are positive integers greater than one that are evenly divisible only by themselves and one. Composite numbers are positive integers that have divisors other than themselves and one.

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## Is the number 121 a prime number?

A:

Full Answer >**The number 121 is not a prime number.**A prime number must have only two factors, 1 and the number itself. However, the number 121 has three factors as 11 is a also factor of 121 in addition to 1 and 121 itself.Filed Under: - Q:
## Is the number 37 a prime number?

A:The number 37 is a prime number. The definition of a prime number is any positive number that can only be divided by the number one or itself. A prime number must also be a whole number larger than the value of one.

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## Is 47 a prime number?

A:The number 47 is a prime. That means that its only positive factors are itself and 1. In other words, it cannot be divided evenly by any other numbers.

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