Thank you, @IPCommerceFan
this is what I have done - i thought i figure it out 😌
/^([1-9].?[4-9]|[2-9](.?[0-9])?)$/
But actually, I am struggling to do the minimum of 1.40;
because now its accept minimum of 1.4 but reject 1.40
if you can help me, I would appreciate it.