A set is a well-defined collection of objects. Each object in a set is called an element of the set. Two sets are equal if they have exactly the same elements in them.
A set is a subset of another set if all elements of the set are elements of the set . In other words, the set is contained inside the set . The subset relationship is denoted as A ⊂ B .The relationship of one set being a subset of another is also called inclusion or we can say Set B may have more elements than A does.
Option 4 .Set B may have more elements than A does is the right answer.
So it is really easy to solve firstly we can see how much does the first 10 boxes make which makes around 55$ obviously. Secondly 45$ for the next 10 boxes.
So for now we can simply calculate that we have spent around 100$ which means 20 boxes. The remaining money left is 77$ so we can buy 77/3.5 = 22 only 22 boxes with that money. Hence a total of 42 boxes.
The math I used is probably not the quickest way, but for me, the easiest. 25*5=125 25+20=45 45*7=315 125+315=440 25*4=100 440+100=540 5+7+4=16 B is your answer.
