The half -life period of a radioactive element x is same as the mean life time of another radioactive element y. Initially both of them have the same number of atoms, Then -
x and y have the same decay rate init ally.
x and y decay at the same rate always
y will decay at a faster rate thaw x
x will decay at a faster rate than y.
Initally number of atoms (N) of both are equal but since therefore, y will decay at a faster rate than x.