Order these weights from lightest to heaviest 10 ounces 1 pound and 1 ounce

It will go from 1 ounce then 10 ounces and then 1 pound, ounces are smaller than ounds so you obviously know from an instant that pounds will be the last one now you have to decide with ounce comes first, well 1 is smaller than 10 so that would be the first. that is how I got my answer

Hope this helped

3x+9+4x+x=8x+9that's the answer for your question.