Here is a simple example, for two hearts (not doubled) making three:
- +50 for making a part-score
- +30 for your seventh trick
- +30 for your eighth trick
- +30 for your ninth trick
Equals 140.
A complex example, for two clubs redoubled and vulnerable, making with two overtricks:
- +100 for making a redoubled contract (the ‘insult’)
- +500 game bonus
- +80 for your seventh trick (minor suit = 20, redoubled = x 4)
- +80 for your eight trick (same)
- +400 for your ninth trick (redoubled overtrick, vulnerable)
- +400 for your tenth trick (same)
Equals the 1560 we mentioned earlier.
There’s a very nice Wikipedia article on Bridge Scoring; we recommend it. But a warning: it’s almost surely more than you want to know. The article includes some information on the history of scoring (there have been some changes over the years).