In[117]:= v=124.58061;
v1=v-0.00024;
v2=v+0.00024;
In[120]:= FullForm[v]
FullForm[v1]
FullForm[v2]
Out[120]//FullForm= 124.58061`
Out[121]//FullForm= 124.58036999999999`
Out[122]//FullForm= 124.58085`
In[123]:= FullForm[Interval[{v1,v2}]]
Out[123]//FullForm= Interval[List[124.58036999999997`,124.58085000000001`]]