Science Insider
Have you ever tried putting an apple in water?
Vidunenahawula Website (National Institute of Fundamental Studies)

Have you ever tried putting an apple in water? If you have, you probably know that they float in water. Apples can float because 25% of their volume is air. This makes apples less dense than water, so they float. An apple and a tipitip packet weigh around 100g. So, if you complain about tipitip packets having a high air content, think about how much air comes with one apple.