This problem involves calculating the total number of matches played in a tournament where every team plays every other team twice.
Determine the number of teams involved. Let $n$ be the number of teams. Given: $n = 10$.
Calculate the number of matches. Each team needs to play against the other $n-1$ teams. Since every team plays each of the other teams twice, we can calculate the total matches using the formula: Total Matches $= n \times (n-1)$
Substitute the value of $n$ into the formula. Total Matches $= 10 \times (10-1)$ Total Matches $= 10 \times 9$ Total Matches $= 90$
Therefore, the total number of matches to be played is 90.
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 ?
Bob is studying the effect of coral and sponge species on reef ecosystems using experiments in artificial square tanks. In each tank, he places 3 species of corals and 2 species of sponges. If there are 6 species of corals and 5 species of sponges to choose from, the minimum number of tanks required to test all combinations of 3 coral and 2 sponge species is _______
(Answer in integer)