1 STATE
DA VINCI DECATHLON 2021 CELEBRATING THE ACADEMIC GIFTS OF STUDENTS IN YEARS 9, 10 & 11
MATHEMATICS
TEAM NUMBER
_____________
1 2
3 4
Total Rank /9
/16
/16
/9
/50
Task developed by Giacomo Rotolo-Ross, University of Sydney, 20202
QUESTION ONE ROLL UP, ROLL UP
9 MARKS When
one thinks of numbers and
βchanceβ, a dice is the first thing that comes to mind. Almost everyone,
it can be said with certainty, will picture ab six-sided one.
Dice with more or less sides do exist but are
very uncommon, and at the most they might have a few extra sides β perhaps 12 at the maximum.
Dice Lab, however,
a small Arizonan company, had other ideas, and set about
creating a sided dice back in 2016. The mathematical name for this shape is ab disdyakis triacontahedron, and this is
the focus of the present task 1. How many edges does a disdyakis triacontahedron have ______________
(1 mark) 2. How many vertices does the shape have _______________
(1 mark) 3. What type of triangles are the faces _______________
(1 mark) 4. Which feature of the shape does the equation below represent _________
(1 mark) 180 11 (5 + 4
β5)
5. Which feature of the shape does the equation below represent ________
(1 mark) 180 11
οΏ½179 β 24β5 6. Complete the equation, which represents the number of possible combinations of numbers from 1 to 120 that
could be placed on the shape, by inserting a number in the brackets
(3 marks).
ππ = 10
( )
7. The above number is greater than the estimated number of atoms in the universe. True or false _________________
(1 mark)