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"Ciento" is an adjective which is often translated as "a hundred", and "cien por ciento" is a phrase which is often translated as "one hundred percent". Learn more about the difference between "ciento" and "cien por ciento" below.
ciento(
syehn
-
toh
)An adjective is a word that describes a noun (e.g., the big dog).
1. (number)
a. a hundred
Hay ciento veinte estudiantes en el grupo.There are a hundred and twenty students in the group.
b. one hundred
Hay ciento cuarenta y cuatro huevos en la caja.There are one hundred forty-four eggs in the box.
2. (colloquial) (number)
A word or phrase that is commonly used in conversational speech (e.g., skinny, grandma).
a. one hundredth
Nuestra ciudad celebra su ciento año como capital del estado este año.Our city celebrates its one hundredth year as state capital this year.
A masculine noun is used with masculine articles and adjectives (e.g., el hombre guapo, el sol amarillo).
cien por ciento(
syehn
pohr
syehn
-
toh
)A phrase is a group of words commonly used together (e.g., once upon a time).
1. (general)
a. one hundred percent
Creo que tienes razón. Te apoyo cien por ciento.I think that you're right. I support you one hundred percent.