martes, 10 de enero de 2017

Answer to the problem of the week: Christmas Tree

The students of the IES Don Bosco are going to make a Christmas Tree using recycled materials. The idea is to make round cardboard trays and to fill them with cans (soft drinks, beer, …). The height of the tree is 216 cm.
The height of a can is 11.5 cm and the thickness of the trays is 5 mm. How many trays will they need to make this tree?

The radius of the top tray is 9.5 cm and the radius of the bottom tray is 69 cm. If the difference between the radiuses of two consecutive trays is always the same, what will be that difference and what will be the radius of each tray?

The sequence of these radiuses is a particular type of sequences. Could you find out the name of these sequences?