In each of 3 rounds of a game, 2 players each lose 5 points. The total change in points is 2 * (-5) * 3. What is the total change?

Explication

In one round 2 losses of 5 points remove 10 points, and 3 such rounds remove 30, so the change sits 30 units below where the score began. Answering 30 states how many points went missing but records the change as a gain, and stopping after 2 of the 3 factors reports only part of the round.