One decade is equal to 10 years.
Decade =10 years
do you mean "decade"? if so then there's 10 years in a decade.
0.3
Neither one makes sense, but "How many days are you?" is grammatically correct.
One quarter
36,500 days. 365x100=36,500 DAYS IN ONE YEAR.
One!
480 days
Seven days in one week
thirty-one days.
11,574 days