The problem asks for the number of ways to select 6 distinct colours from a total of 9 distinct colours. Since the order of the colours does not matter, this is a combination problem.
We need to find the number of combinations of choosing 6 items (colours) from a set of 9 distinct items (Impatiens species). The formula for combinations is:
$C(n, k) = \binom{n}{k} = \frac{n!}{k!(n-k)!}$
Where:
$C(9, 6) = \binom{9}{6} = \frac{9!}{6!(9-6)!}$
$C(9, 6) = \frac{9!}{6!3!} = \frac{9 \times 8 \times 7 \times 6!}{6! \times (3 \times 2 \times 1)}$
$C(9, 6) = \frac{9 \times 8 \times 7}{3 \times 2 \times 1}$
$C(9, 6) = \frac{504}{6} = 84$
Therefore, there are 84 possible colour combinations.
How many ways are there to pack six copies of the same book into four identical boxes, where a box can contain as many as six books ?
Let us assume a person climbing the stairs can take one stair or two stairs at a time. How many ways can this person climb a flight of eight stairs?
There are 9 different rock lizard species, each with a unique colour. Lizards of 2 different species sit on a rock at any given time. The number of possible colour combinations of rock lizards seen together on a rock is _________
(Answer in integer)