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Hi, I am trying to do a question from the pre paper but I just can't get a part of it. This is the question:

"Luke has €320 made up of 50 euro and 10 euro notes. He has 12 notes in total.

(a) By letting x be the number of 50 euro notes and y be the number of 10 euro notes, write down two equations in x and y to represent the above information."

I presume these are simultaneous equations as the next questions says solve the equations to find the number of each type of note Luke has, so I have already gotten the equation 5x+7y=320, but I can't for the life of me come up with a second equation. If anyone could help it would be much appreciated! Thanks! :)

1. #### Ella-S

Im not sure if 5x+7y=320 works? But I think x+y=12 could be one of the equations and 50x+10y=320 is the other :)

2. #### emma1808

You're dead right Ella just tried them equations now and it worked out! Thanks so much! :D

3. #### Dazzla16

Hi Emma! To clear things up, 5x + 7y = 320 will not work. Ella is spot on.

When you come across a question similar to this, here are some tips that can help you:

Make one equation deal with the amount of money (in the case of your question, 50x + 10y = 320 is the equation that deals with the amount of money, because 50 represents the money value in euros and x is the amount of 50 euros there are, and etc.)

Make the other equation deal with the amount of a certain object (in the case of your question, x + y = 12 is the equation that deals with the amount of a certain object, which is the notes. x represents the number of 50 euro notes and y represents the number of 10 euro notes. There are 12 notes in total.)

Thought it wouldn't do any harm giving you extra help :)