One and half hours or one and half hours? RTRT!

One and half hours or one and half hours? RTRT!


one and half a hour
one and a half hours
one hour and a half.
All the above statements are acceptable



A half hours or a half hours?
Is it singular or plural after a half?


All wrong, half an hour and a half



One and a half hours or one and a half hours


one and a half hours