Question 2
Anggi is 140 cm tall and she can grab any object 40 cm above her head. She wants to take a book from the top of a cupboard which is 2.8 meters from the floor. She has several chairs with the same height, which can be stacked without overlap. If she uses one chair and stands on it, the distance between the tip of her hand and the book is 65 cm. What is the minimum number of chairs she needs to use to be able to grab the book?