Percentage question: A contractor deducts 3% discount from an invoice

[Jonbud]

Hi all, this is my first post so please be gentle with me!

I've been preparing for an upcoming online assessment and have been working through some example maths questions in a 'prepare for aptitude tests' book. Here is the problem:

A contractor deducts 3% discount from an invoice and remits £2764.50. For what sum was the invoice made out?

Using my very limited maths skills I divided 2764.50 by 100 to get 27.65. I then multiplied that by three to get 82.95. I added 82.95 to 2764.50 to get the 'answer' of £2847.45. This however appears to be incorrect. I do know the correct answer and now I know it I can work the problem backwards to confirm. But without knowing the correct answer how do you solve this problem?

Cheers,
Jon.

 

[stapel]

A contractor deducts 3% discount from an invoice and remits £2764.50. For what sum was the invoice made out?

Hint: If he took three percent off, then he paid ninety-seven percent. So the amount paid is ninety-seven percent (not one hundred percent) of the amount due.

For further information (and worked examples), try here.