I swear,

my kindness will be the end of me. I finally gather the resolve to study all day today and I see a blinking MSN window.... Mark...? That cousin in Singapore? Wonder what he wants. Turns out he wants help for math...... And his teacher is coming to check in 30 mins. I was like, wtf x_x So, okay, fine, I decide to help. He sends me a document with the question.

The students of E18C decided to hold a barbeque for class gathering and appointed Fred as the organiser.

He decided to engage the services of YumYum, a food catering company to provide the food items for the barbeque.

One day, while attending an IG activity, Fred found out that 5 other IG members – Ash, Bob, Carl, Dan and Ed – had previously engaged the services of YumYum.
During their conversation, they discussed how much each of them had paid for the food items for their barbeques. Fred felt that he might have been charged excessively by YumYum.
Fred bought the following food items for the class barbeque (see Table A below):


Fred felt that a comparison of all their bills could be useful (see Table B below):



Investigate whether Fred has been charged excessively for the food items he bought from YumYum as compared to the other IG members.

And I ended up spending a whole friggin hour on it. Damn those Singaporean kids do some scary stuff for homework.

Try solve it! =) If you don't feel like it, then you could just download the answer here.
Answer

Gaze upon it and be awed. I guarantee you you pengsan. I know I did lol.