Skip to content / Đến nội dung
ThichHocToan.com

MathNet 2011 Question 41

Math Olympiad Vault · MathNet 2011

Question 41

Juku discovered that of the things in his satchel, $60\%$ were ugly and $76\%$ were useless. He scrapped all things that were both ugly and useless, and added things that were both beautiful and useful. After this, of the things in Juku's satchel, $25\%$ are ugly and $45\%$ are useless. How many percent of the things in Juku's satchel were both beautiful and useful initially?

Answer: $4\%$.